922 resultados para order- delivery process


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The new management models have led to the reorganization of institutions today. Much is made in improving the delivery of public services entities, and they have sought to adopt these new initiatives in order to improve the quality of the product or service offered to users. The modernization of the management model at the Federal University of Rio Grande do Norte (UFRN) strengthened by the accession of the institution to GesPública Program, which focuses on the management modernization leading institutions to seek ways to fit to meet the demands proposed the Program. Therefore, the Department of Personnel Administration (DAP) has structured its processes and procedures using the mapping tool processes. This research starts from the question: what were the results obtained with the implementation of the management and process mapping of PAD? It is proposed as a general objective to analyze the management and the mapping of that Board processes, identifying the possible benefits in improving the quality of the services provided to users. The specific objectives to achieve results, are pointed out: describe how you carried out the implementation of the management and process mapping in DAP and how it is working at the moment; examine the line in the relationship between the actions developed by the DAP and modern theories of this theme; identify the evolution of the sector with the measures adopted and the results obtained with the implementation of the mapping tool. In the theoretical framework, it was approached a brief history of the evolution of public administration in Brazil, GesPública program and its importance for process management in public institutions as well as the Management and Process Mapping. The context of the study was the DAP, and participants were managers of the institution in the survey. Data collection was done through the study of the institution's documents, bibliography analysis available on the topic, questionnaires and semi-structured interviews with professionals of the institution involved with the object of study, since its inception until July 2015, when it was finished the search. As a result, were listed: the motivation, importance, benefits and innovations that management and the mapping of processes brought to the institution, point out what has been improved in the service users and the tools used. We also analyze the main problems identified during the implementation of the mapping. As a suggestion, it was analyzed how these procedures can, if possible, be extended to other sectors of UFRN.

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Maternity nursing practice is changing across Canada with the movement toward becoming “baby friendly.” The World Health Organization (WHO) recommends the Baby-Friendly Hospital Initiative (BFHI) as a standard of care in hospitals worldwide. Very little research has been conducted with nurses to explore the impact of the initiative on nursing practice. The purpose of this study, therefore, was to examine the process of implementing the BFHI for nurses. The study was carried out using Corbin and Strauss’s method of grounded theory. Theoretical sampling was employed, which resulted in recruiting and interviewing 13 registered nurses whose area of employment included neonatal intensive care, postpartum, and labour and delivery. The data analysis revealed a central category of resisting the BFHI. All of the nurses disagreed with some of the 10 steps to becoming a baby-friendly hospital as outlined by the WHO. Participants questioned the science and safety of aspects of the BFHI. Also, participants indicated that the implementation of this program did not substantially change their nursing practice. They empathized with new mothers and anticipated being collectively reprimanded by management should they not follow the initiative. Five conditions influenced their responses to the initiative, which were (a) an awareness of a pro-breastfeeding culture, (b) imposition of the BFHI, (c) knowledge of the health benefits of breastfeeding, (d) experiential knowledge of infant feeding, and (e) the belief in the autonomy of mothers to decide about infant feeding. The identified outcomes were moral distress and division between nurses. The study findings could guide decision making concerning the implementation of the BFHI.

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In the Flux Cored Arc Welding (FCAW) process, the transfer of filler metal (metal transfer modes) to the base material to accomplish the weld bead determines the weld quality and therefore studies of such phenomena is demanded. Thus, in this work, the metal transfer through the FCAW process is investigated by filming the phenomena with the assist of near infrared visualization. During the literature survey, it was found that this technic has not been used so far for analyzing the FCAW process. It must be pointed out that the radiation emitted from the weld arc, fumes and particles (spattering) in this process represent a barrier for these studies based in the process visualization. The monitoring of metal transfer for FCAW process was carried out within the operational envelope of voltage and wire feed speed with the electrode E71T-1 (1.2 mm diameter) and Ar+25%CO2 as a shielding gas. A local developed near infrared filming with frame rate of 300 Hz was employed for metal transfer visualization in order to contribute to a better understanding of this process and evaluating characteristics of metal transfer, unlike previous studies, which used shadowgraph technique. It can clearly be seen how the droplet is created and transferred in this process and also identify the different modes of metal transfer by changing the parameters of voltage and wire feed speed in metal transfer maps. The final result of this study is the metal transfer mode maps, which establish suitable conditions and provide the basis for developing arc control strategies for the FCAW process.

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Inscriptions: Verso: [stamped] Photograph by Freda Leinwand. [463 West Street, Studio 229G, New York, NY 10014].

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L’estradiol (E2) est une hormone femelle qui joue un rôle essentiel, à la fois dans la régulation et dans la détermination de certaines conditions physiologiques in vivo, telle que la différenciation et la prolifération cellulaire. Lorsque l’E2 est donné en supplément, par exemple dans le cas de thérapie hormonale, deux effets sont observés, un effet génomique et un effet non-génomique, de par son interaction avec les récepteurs à œstrogène du noyau ou de la membrane cellulaire, respectivement. L’effet non-génomique est plus difficile à étudier biologiquement parce que l’effet se produit sur une échelle de temps extrêmement courte et à cause de la nature hydrophobe de l’E2 qui réduit sa biodisponibilité et donc son accessibilité aux cellules cibles. C’est pourquoi il est nécessaire de développer des systèmes d’administration de l’E2 qui permettent de n’étudier que l’effet non-génomique de l’œstrogène. Une des stratégies employée consiste à greffer l’E2 à des macromolécules hydrophiles, comme de l’albumine de sérum bovin (BSA) ou des dendrimères de type poly(amido)amine, permettant de maintenir l’interaction de l’E2 avec les récepteurs d’œstrogène de la membrane cellulaire et d’éviter la pénétration de l’E2 dans le noyau des cellules. Toutefois, ces systèmes macromolécules-E2 sont critiquables car ils sont peu stables et l’E2 peut se retrouver sous forme libre, ce qui affecte sa localisation cellulaire. L’objectif de cette thèse est donc de développer de nouvelles plateformes fonctionnalisées avec de l’E2 en utilisant les approches de synthèses ascendantes et descendantes. Le but de ces plateformes est de permettre d’étudier le mécanisme de l’effet non-génomique de l’E2, ainsi que d’explorer des applications potentielles dans le domaine biomédical. L’approche ascendante est basée sur un ligand d’E2 activé, l’acide 17,α-éthinylestradiol-benzoïque, attaché de façon covalente à un polymère de chitosan avec des substitutions de phosphorylcholine (CH-PC-E2). L’estradiol est sous forme de pro-drogue attachée au polymère qui s’auto-assembler pour former un film. L’effet biologique de la composition chimique du film de chitosan-phosphorylcholine a été étudié sur des cellules endothéliales. Les films de compositions chimiques différentes ont préalablement été caractérisés de façon physicochimique. La topographie de la surface, la charge de surface, ainsi que la rhéologie des différents films contenant 15, 25, ou 40% molaires de phosphorylcholine, ont été étudiés par microscopie à force atomique (AFM), potentiel zêta, résonance plasmonique de surface et par microbalance à cristal de quartz avec dissipation (QCM-D). Les résultats de QCM-D ont montré que plus la part molaire en phosphorylcholine est grande moins il y a de fibrinogène qui s’adsorbe sur le film de CH-PC. Des cellules humaines de veine ombilicale (HUVECs) cultivées sur des films de CH-PC25 et de CH-PC40 forment des amas cellulaire appelés sphéroïdes au bout de 4 jours, alors que ce n’est pas le cas lorsque ces cellules sont cultivées sur des films de CH-PC15. L’attachement de l’estradiol au polymère a été caractérisé par plusieurs techniques, telles que la résonance magnétique nucléaire de proton (1H NMR), la spectroscopie infrarouge avec transformée de Fourier à réfraction totale atténuée (FTIR-ATR) et la spectroscopie UV-visible. La nature hydrogel des films (sa capacité à retenir l’eau) ainsi que l’interaction des films avec des récepteurs à E2, ont été étudiés par la QCM-D. Des études d’imagerie cellulaires utilisant du diacétate de diaminofluoresceine-FM ont révélé que les films hydrogels de CH-PC-E2 stimulent la production d’oxyde nitrique par les cellules endothéliales, qui joue un rôle protecteur pour le système cardiovasculaire. L’ensemble de ces études met en valeur les rôles différents et les applications potentielles qu’ont les films de type CH-PC-E2 et CH-PC dans le cadre de la médecine cardiovasculaire régénérative. L’approche descendante est basée sur l’attachement de façon covalente d’E2 sur des ilots d’or de 2 μm disposés en rangées et espacés par 12 μm sur un substrat en verre. Les ilots ont été préparés par photolithographie. La surface du verre a quant à elle été modifiée à l’aide d’un tripeptide cyclique, le cRGD, favorisant l’adhésion cellulaire. L’attachement d’E2 sur les surfaces d’or a été suivi et confirmé par les techniques de SPR et de QCM-D. Des études d’ELISA ont montré une augmentation significative du niveau de phosphorylation de la kinase ERK (marqueur important de l’effet non-génomique) après 1 heure d’exposition des cellules endothéliales aux motifs alternant l’E2 et le cRGD. Par contre lorsque des cellules cancéreuses sont déposées sur les surfaces présentant des motifs d’E2, ces cellules ne croissent pas, ce qui suggère que l’E2 n’exerce pas d’effet génomique. Les résultats de l’approche descendante montrent le potentiel des surfaces présentant des motifs d’E2 pour l’étude des effets non-génomiques de l’E2 dans un modèle in vitro.

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The application of pharmacokinetic modelling within the drug development field essentially allows one to develop a quantitative description of the temporal behaviour of a compound of interest at a tissue/organ level, by identifying and defining relationships between a dose of a drug and dependent variables. In order to understand and characterise the pharmacokinetics of a drug, it is often helpful to employ pharmacokinetic modelling using empirical or mechanistic approaches. Pharmacokinetic models can be developed within mathematical and statistical commercial software such as MATLAB using traditional mathematical and computation coding, or by using the Simbiology Toolbox available within MATLAB for a graphical user interface approach to developing pharmacokinetic (PBPK) models. For formulations dosed orally, a prerequisite for clinical activity is the entry of the drug into the systemic circulation.

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Aircraft manufacturing industries are looking for solutions in order to increase their productivity. One of the solutions is to apply the metrology systems during the production and assembly processes. Metrology Process Model (MPM) (Maropoulos et al, 2007) has been introduced which emphasises metrology applications with assembly planning, manufacturing processes and product designing. Measurability analysis is part of the MPM and the aim of this analysis is to check the feasibility for measuring the designed large scale components. Measurability Analysis has been integrated in order to provide an efficient matching system. Metrology database is structured by developing the Metrology Classification Model. Furthermore, the feature-based selection model is also explained. By combining two classification models, a novel approach and selection processes for integrated measurability analysis system (MAS) are introduced and such integrated MAS could provide much more meaningful matching results for the operators. © Springer-Verlag Berlin Heidelberg 2010.

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A new modality for preventing HIV transmission is emerging in the form of topical microbicides. Some clinical trials have shown some promising results of these methods of protection while other trials have failed to show efficacy. Due to the relatively novel nature of microbicide drug transport, a rigorous, deterministic analysis of that transport can help improve the design of microbicide vehicles and understand results from clinical trials. This type of analysis can aid microbicide product design by helping understand and organize the determinants of drug transport and the potential efficacies of candidate microbicide products.

Microbicide drug transport is modeled as a diffusion process with convection and reaction effects in appropriate compartments. This is applied here to vaginal gels and rings and a rectal enema, all delivering the microbicide drug Tenofovir. Although the focus here is on Tenofovir, the methods established in this dissertation can readily be adapted to other drugs, given knowledge of their physical and chemical properties, such as the diffusion coefficient, partition coefficient, and reaction kinetics. Other dosage forms such as tablets and fiber meshes can also be modeled using the perspective and methods developed here.

The analyses here include convective details of intravaginal flows by both ambient fluid and spreading gels with different rheological properties and applied volumes. These are input to the overall conservation equations for drug mass transport in different compartments. The results are Tenofovir concentration distributions in time and space for a variety of microbicide products and conditions. The Tenofovir concentrations in the vaginal and rectal mucosal stroma are converted, via a coupled reaction equation, to concentrations of Tenofovir diphosphate, which is the active form of the drug that functions as a reverse transcriptase inhibitor against HIV. Key model outputs are related to concentrations measured in experimental pharmacokinetic (PK) studies, e.g. concentrations in biopsies and blood. A new measure of microbicide prophylactic functionality, the Percent Protected, is calculated. This is the time dependent volume of the entire stroma (and thus fraction of host cells therein) in which Tenofovir diphosphate concentrations equal or exceed a target prophylactic value, e.g. an EC50.

Results show the prophylactic potentials of the studied microbicide vehicles against HIV infections. Key design parameters for each are addressed in application of the models. For a vaginal gel, fast spreading at small volume is more effective than slower spreading at high volume. Vaginal rings are shown to be most effective if inserted and retained as close to the fornix as possible. Because of the long half-life of Tenofovir diphosphate, temporary removal of the vaginal ring (after achieving steady state) for up to 24h does not appreciably diminish Percent Protected. However, full steady state (for the entire stromal volume) is not achieved until several days after ring insertion. Delivery of Tenofovir to the rectal mucosa by an enema is dominated by surface area of coated mucosa and whether the interiors of rectal crypts are filled with the enema fluid. For the enema 100% Percent Protected is achieved much more rapidly than for vaginal products, primarily because of the much thinner epithelial layer of the mucosa. For example, 100% Percent Protected can be achieved with a one minute enema application, and 15 minute wait time.

Results of these models have good agreement with experimental pharmacokinetic data, in animals and clinical trials. They also improve upon traditional, empirical PK modeling, and this is illustrated here. Our deterministic approach can inform design of sampling in clinical trials by indicating time periods during which significant changes in drug concentrations occur in different compartments. More fundamentally, the work here helps delineate the determinants of microbicide drug delivery. This information can be the key to improved, rational design of microbicide products and their dosage regimens.

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Background: The burden of mental health is increased in humanitarian settings, and needs to be addressed in emergency situations. The World Health Organization has recently released the mental health Global Action Programme Humanitarian Intervention Guide (mhGAP-HIG) in order to scale up mental health service delivery in humanitarian settings through task-shifting. This study aims to evaluate, contextualize and identify possible barriers and challenges to mhGAP-HIG manual content, training and implementation in post-earthquake Nepal.

Methods: This qualitative study was conducted in Kathmandu, Nepal. Key informant interviews were conducted with fourteen psychiatrists involved in a mhGAP-HIG Training of Trainers and Supervisors (ToTS) in order to assess the mhGAP-HIG, ToTS training, and the potential challenges and barriers to mhGAP-HIG implementation. Themes identified by informants were supplemented by process notes taken by the researcher during observed training sessions and meetings.

Results: Key themes emerging from key informant interviews include the need to take three factors into account in manual contextualization: culture, health systems and the humanitarian setting. This includes translation of the manual into the local language, adding or expanding upon conditions prevalent in Nepal, and more consideration to improving feasibility of manual use by non-specialists.

Conclusion: The mhGAP-HIG must be tailored to specific humanitarian settings for effective implementation. This study shows the importance of conducting a manual contextualization workshop prior to training in order to maximize the feasibility and success in training health care workers in mhGAP.

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A RET network consists of a network of photo-active molecules called chromophores that can participate in inter-molecular energy transfer called resonance energy transfer (RET). RET networks are used in a variety of applications including cryptographic devices, storage systems, light harvesting complexes, biological sensors, and molecular rulers. In this dissertation, we focus on creating a RET device called closed-diffusive exciton valve (C-DEV) in which the input to output transfer function is controlled by an external energy source, similar to a semiconductor transistor like the MOSFET. Due to their biocompatibility, molecular devices like the C-DEVs can be used to introduce computing power in biological, organic, and aqueous environments such as living cells. Furthermore, the underlying physics in RET devices are stochastic in nature, making them suitable for stochastic computing in which true random distribution generation is critical.

In order to determine a valid configuration of chromophores for the C-DEV, we developed a systematic process based on user-guided design space pruning techniques and built-in simulation tools. We show that our C-DEV is 15x better than C-DEVs designed using ad hoc methods that rely on limited data from prior experiments. We also show ways in which the C-DEV can be improved further and how different varieties of C-DEVs can be combined to form more complex logic circuits. Moreover, the systematic design process can be used to search for valid chromophore network configurations for a variety of RET applications.

We also describe a feasibility study for a technique used to control the orientation of chromophores attached to DNA. Being able to control the orientation can expand the design space for RET networks because it provides another parameter to tune their collective behavior. While results showed limited control over orientation, the analysis required the development of a mathematical model that can be used to determine the distribution of dipoles in a given sample of chromophore constructs. The model can be used to evaluate the feasibility of other potential orientation control techniques.

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Establishment of the intestinal microbiota commences at birth and this colonisation is influenced by a number of factors including mode of delivery, gestational age, mode of feeding, environmental factors and host genetics. As this initial establishment may well influence the health of an individual later in life, it is imperative to understand this process. Therefore, this thesis set out to investigate how early infant nutrition influences the development of a healthy gut microbiota. As part of the INFANTMET project, the intestinal microbiota of 199 breastfed infants was investigated using both culture-dependent and culture-independent approaches. This study revealed that delivery mode and gestational age had a significant impact on early microbial communities. In order to understand host genotype-microbiota interactions, the gut microbiota composition of dichorionic triplets was also investigated. The results suggested that initially host genetics play a significant role in the composition of an individual’s gut microbiota, but by month 12 environmental factors are the major determinant. To investigate the origin of hydrogen sulphide in a case of nondrug- induced sulfhemoglobinemia in a preterm infant, the gut microbiota composition was determined. This analysis revealed the presence of Morganella morganii, a producer of hydrogen sulphide and hemolysins, at a relative abundance 38%, which was not detected in control infants. Following on from this, the negative and short term consequences of intrapartum antibiotic prophylaxis exposure on the early infant intestinal microbiota composition were demonstrated, particularly in breast-fed infants, which are recovered by day 30. Finally, the composition of the breast milk microbiota over the first three months of life was characterised. A core of 12 genera were identified amongst women and the remainder comprised some 195 genera which were individual specific and subject to variations over time. The results presented in this thesis have demonstrated that the development of the infant gut microbiota is complex and highly individual. Clear alterations in the intestinal microbiota establishment process in C-section delivered, preterm and antibiotic exposed infants were shown. Taken together, long-term health benefits for infants, particularly those vulnerable groups, may be conferred through the design of probiotic and prebiotic food ingredients and supplements.

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Prostate cancer is one of the most common cancers diagnosed in men. Whilst treatments for early-stage disease are largely effective, current therapies for metastatic prostate cancer, particularly for bone metastasis, offer only a few months increased lifespan at best. Hence new treatments are urgently required. Small interfering RNA (siRNA) has been investigated for the treatment of prostate cancer where it can ‘silence’ specific cancer-related genes. However the clinical application of siRNA-based gene therapy is limited due to the absence of an optimised gene delivery vector. The optimisation of such gene delivery vectors is routinely undertaken in vitro using 2D cell culture on plastic dishes which does not accurately simulate the in vivo bone cancer metastasis microenvironment. The goal of this thesis was to assess the potential of two different targeted delivery vectors (gold or modified β-cyclodextrin derivatives) to facilitate siRNA receptor-mediated uptake into prostate cancer cells. Furthermore, this project aimed to develop a more physiologically relevant 3D in vitro cell culture model, to mimic prostate cancer bone metastasis, which is suitable for evaluating the delivery of nanoparticulate gene therapeutics. In the first instance, cationic derivatives of gold and β-cyclodextrin were synthesized to complex anionic siRNA. The delivery vectors were targeted to prostate cancer cells using the anisamide ligand which has high affinity for the sigma receptor that is overexpressed by prostate cancer cells. The gold nanoparticle demonstrated high levels of uptake into prostate cancer PC3 cells and efficient gene silencing when transfection was performed in serum-free media. However, due to the absence of a poly(ethylene glycol) (PEG) stabilising group, the formulation was unsuitable for use in serum-containing conditions. Conversely, the modified β-cyclodextrin formulation demonstrated enhanced stability in the presence of serum due to the inclusion of a PEG chain onto which the anisamide ligand was conjugated. However, the maximum level of gene silencing efficacy from three different prostate cancer cell lines (DU145, VCaP and PC3 cells) was 30 %, suggesting that further optimisation of the formulation would be required prior to application in vivo. In order to develop a more physiologically-relevant in vitro model of prostate cancer bone metastasis, prostate cancer cells (PC3 and LNCaP cells) were cultured in 3D on collagenbased scaffolds engineered to mimic the bone microenvironment. While the model was suitable for assessing nanoparticle-mediated gene knockdown, prostate cancer cells demonstrated a phenotype with lower invasive potential when grown on the scaffolds relative to standard 2D cell culture. Hence, prostate cancer cells (PC3 and LNCaP cells) were subsequently co-cultured with bone osteoblast cells (hFOB 1.19 cells) to enhance the physiological relevance of the model. Co-cultures secreted elevated levels of the MMP9 enzyme, a marker of prostate cancer metastasis, relative to prostate cancer cell monocultures (2D and 3D) indicating enhanced physiological relevance of the model. Furthermore, the coculture model proved suitable for investigating nanoparticle-mediated gene silencing. In conclusion, the work outlined in this thesis identified two different sigma receptor-targeted gene delivery vectors with potential for the treatment of prostate cancer. In addition, a more physiologically relevant model of prostate cancer bone metastasis was developed with the capacity to help optimise gene delivery vectors for the treatment of prostate cancer.

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L’estradiol (E2) est une hormone femelle qui joue un rôle essentiel, à la fois dans la régulation et dans la détermination de certaines conditions physiologiques in vivo, telle que la différenciation et la prolifération cellulaire. Lorsque l’E2 est donné en supplément, par exemple dans le cas de thérapie hormonale, deux effets sont observés, un effet génomique et un effet non-génomique, de par son interaction avec les récepteurs à œstrogène du noyau ou de la membrane cellulaire, respectivement. L’effet non-génomique est plus difficile à étudier biologiquement parce que l’effet se produit sur une échelle de temps extrêmement courte et à cause de la nature hydrophobe de l’E2 qui réduit sa biodisponibilité et donc son accessibilité aux cellules cibles. C’est pourquoi il est nécessaire de développer des systèmes d’administration de l’E2 qui permettent de n’étudier que l’effet non-génomique de l’œstrogène. Une des stratégies employée consiste à greffer l’E2 à des macromolécules hydrophiles, comme de l’albumine de sérum bovin (BSA) ou des dendrimères de type poly(amido)amine, permettant de maintenir l’interaction de l’E2 avec les récepteurs d’œstrogène de la membrane cellulaire et d’éviter la pénétration de l’E2 dans le noyau des cellules. Toutefois, ces systèmes macromolécules-E2 sont critiquables car ils sont peu stables et l’E2 peut se retrouver sous forme libre, ce qui affecte sa localisation cellulaire. L’objectif de cette thèse est donc de développer de nouvelles plateformes fonctionnalisées avec de l’E2 en utilisant les approches de synthèses ascendantes et descendantes. Le but de ces plateformes est de permettre d’étudier le mécanisme de l’effet non-génomique de l’E2, ainsi que d’explorer des applications potentielles dans le domaine biomédical. L’approche ascendante est basée sur un ligand d’E2 activé, l’acide 17,α-éthinylestradiol-benzoïque, attaché de façon covalente à un polymère de chitosan avec des substitutions de phosphorylcholine (CH-PC-E2). L’estradiol est sous forme de pro-drogue attachée au polymère qui s’auto-assembler pour former un film. L’effet biologique de la composition chimique du film de chitosan-phosphorylcholine a été étudié sur des cellules endothéliales. Les films de compositions chimiques différentes ont préalablement été caractérisés de façon physicochimique. La topographie de la surface, la charge de surface, ainsi que la rhéologie des différents films contenant 15, 25, ou 40% molaires de phosphorylcholine, ont été étudiés par microscopie à force atomique (AFM), potentiel zêta, résonance plasmonique de surface et par microbalance à cristal de quartz avec dissipation (QCM-D). Les résultats de QCM-D ont montré que plus la part molaire en phosphorylcholine est grande moins il y a de fibrinogène qui s’adsorbe sur le film de CH-PC. Des cellules humaines de veine ombilicale (HUVECs) cultivées sur des films de CH-PC25 et de CH-PC40 forment des amas cellulaire appelés sphéroïdes au bout de 4 jours, alors que ce n’est pas le cas lorsque ces cellules sont cultivées sur des films de CH-PC15. L’attachement de l’estradiol au polymère a été caractérisé par plusieurs techniques, telles que la résonance magnétique nucléaire de proton (1H NMR), la spectroscopie infrarouge avec transformée de Fourier à réfraction totale atténuée (FTIR-ATR) et la spectroscopie UV-visible. La nature hydrogel des films (sa capacité à retenir l’eau) ainsi que l’interaction des films avec des récepteurs à E2, ont été étudiés par la QCM-D. Des études d’imagerie cellulaires utilisant du diacétate de diaminofluoresceine-FM ont révélé que les films hydrogels de CH-PC-E2 stimulent la production d’oxyde nitrique par les cellules endothéliales, qui joue un rôle protecteur pour le système cardiovasculaire. L’ensemble de ces études met en valeur les rôles différents et les applications potentielles qu’ont les films de type CH-PC-E2 et CH-PC dans le cadre de la médecine cardiovasculaire régénérative. L’approche descendante est basée sur l’attachement de façon covalente d’E2 sur des ilots d’or de 2 μm disposés en rangées et espacés par 12 μm sur un substrat en verre. Les ilots ont été préparés par photolithographie. La surface du verre a quant à elle été modifiée à l’aide d’un tripeptide cyclique, le cRGD, favorisant l’adhésion cellulaire. L’attachement d’E2 sur les surfaces d’or a été suivi et confirmé par les techniques de SPR et de QCM-D. Des études d’ELISA ont montré une augmentation significative du niveau de phosphorylation de la kinase ERK (marqueur important de l’effet non-génomique) après 1 heure d’exposition des cellules endothéliales aux motifs alternant l’E2 et le cRGD. Par contre lorsque des cellules cancéreuses sont déposées sur les surfaces présentant des motifs d’E2, ces cellules ne croissent pas, ce qui suggère que l’E2 n’exerce pas d’effet génomique. Les résultats de l’approche descendante montrent le potentiel des surfaces présentant des motifs d’E2 pour l’étude des effets non-génomiques de l’E2 dans un modèle in vitro.

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Geomorphic process units have been derived in order to allow quantification via GIS techniques at a catchment scale. Mass movement rates based on existing field measurements are employed in the budget calculations. In the Kärkevagge catchment, Northern Sweden, 80% of the area can be identified either as a source area for sediments or as a zone where sediments are deposited. The overall budget for the slopes beneath the rockwalls in the Kärkevagge is approximately 680 t/a whilst about 150 t a-1 are transported into the fluvial system.

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Recent debate on the quality of arts events has concentrated on the requirement to deliver against a complex range of political, social, and cultural criteria with an emphasis on the external partnerships that are forged. Yet those aspects of quality over which event organizers have more direct control have been accorded minor examination. The authors believe that operational effectiveness is key to service quality in the cultural context, and seek to demonstrate that a balanced consideration of both process and product is vital to fully deliver quality arts events. This article identifies areas of emergent research and practice and focuses on issues in the front-of-house environment where the breakdown of service quality is a real concern, using the experience of one UK not-for-profit arts organization as a case study to illustrate potential management responses.