942 resultados para Current Density Mapping Method


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Dans le contexte climatique actuel, les régions méditerranéennes connaissent une intensification des phénomènes hydrométéorologiques extrêmes. Au Maroc, le risque lié aux inondations est devenu problématique, les communautés étant vulnérables aux événements extrêmes. En effet, le développement économique et urbain rapide et mal maîtrisé augmente l'exposition aux phénomènes extrêmes. La Direction du Développement et de la Coopération suisse (DDC) s'implique activement dans la réduction des risques naturels au Maroc. La cartographie des dangers et son intégration dans l'aménagement du territoire représentent une méthode efficace afin de réduire la vulnérabilité spatiale. Ainsi, la DDC a mandaté ce projet d'adaptation de la méthode suisse de cartographie des dangers à un cas d'étude marocain (la ville de Beni Mellal, région de Tadla-Azilal, Maroc). La méthode suisse a été adaptée aux contraintes spécifiques du terrain (environnement semi-aride, morphologie de piémont) et au contexte de transfert de connaissances (caractéristiques socio-économiques et pratiques). Une carte des phénomènes d'inondations a été produite. Elle contient les témoins morphologiques et les éléments anthropiques pertinents pour le développement et l'aggravation des inondations. La modélisation de la relation pluie-débit pour des événements de référence, et le routage des hydrogrammes de crue ainsi obtenus ont permis d'estimer quantitativement l'aléa inondation. Des données obtenues sur le terrain (estimations de débit, extension de crues connues) ont permis de vérifier les résultats des modèles. Des cartes d'intensité et de probabilité ont été obtenues. Enfin, une carte indicative du danger d'inondation a été produite sur la base de la matrice suisse du danger qui croise l'intensité et la probabilité d'occurrence d'un événement pour obtenir des degrés de danger assignables au territoire étudié. En vue de l'implémentation des cartes de danger dans les documents de l'aménagement du territoire, nous nous intéressons au fonctionnement actuel de la gestion institutionnelle du risque à Beni Mellal, en étudiant le degré d'intégration de la gestion et la manière dont les connaissances sur les risques influencent le processus de gestion. L'analyse montre que la gestion est marquée par une logique de gestion hiérarchique et la priorité des mesures de protection par rapport aux mesures passives d'aménagement du territoire. Les connaissances sur le risque restent sectorielles, souvent déconnectées. L'innovation dans le domaine de la gestion du risque résulte de collaborations horizontales entre les acteurs ou avec des sources de connaissances externes (par exemple les universités). Des recommandations méthodologiques et institutionnelles issues de cette étude ont été adressées aux gestionnaires en vue de l'implémentation des cartes de danger. Plus que des outils de réduction du risque, les cartes de danger aident à transmettre des connaissances vers le public et contribuent ainsi à établir une culture du risque. - Severe rainfall events are thought to be occurring more frequently in semi-arid areas. In Morocco, flood hazard has become an important topic, notably as rapid economic development and high urbanization rates have increased the exposure of people and assets in hazard-prone areas. The Swiss Agency for Development and Cooperation (SADC) is active in natural hazard mitigation in Morocco. As hazard mapping for urban planning is thought to be a sound tool for vulnerability reduction, the SADC has financed a project aimed at adapting the Swiss approach for hazard assessment and mapping to the case of Morocco. In a knowledge transfer context, the Swiss method was adapted to the semi-arid environment, the specific piedmont morphology and to socio-economic constraints particular to the study site. Following the Swiss guidelines, a hydro-geomorphological map was established, containing all geomorphic elements related to known past floods. Next, rainfall / runoff modeling for reference events and hydraulic routing of the obtained hydrographs were carried out in order to assess hazard quantitatively. Field-collected discharge estimations and flood extent for known floods were used to verify the model results. Flood hazard intensity and probability maps were obtained. Finally, an indicative danger map as defined within the Swiss hazard assessment terminology was calculated using the Swiss hazard matrix that convolves flood intensity with its recurrence probability in order to assign flood danger degrees to the concerned territory. Danger maps become effective, as risk mitigation tools, when implemented in urban planning. We focus on how local authorities are involved in the risk management process and how knowledge about risk impacts the management. An institutional vulnerability "map" was established based on individual interviews held with the main institutional actors in flood management. Results show that flood hazard management is defined by uneven actions and relationships, it is based on top-down decision-making patterns, and focus is maintained on active mitigation measures. The institutional actors embody sectorial, often disconnected risk knowledge pools, whose relationships are dictated by the institutional hierarchy. Results show that innovation in the risk management process emerges when actors collaborate despite the established hierarchy or when they open to outer knowledge pools (e.g. the academia). Several methodological and institutional recommendations were addressed to risk management stakeholders in view of potential map implementation to planning. Hazard assessment and mapping is essential to an integrated risk management approach: more than a mitigation tool, danger maps represent tools that allow communicating on hazards and establishing a risk culture.

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The large spatial inhomogeneity in transmit B, field (B-1(+)) observable in human MR images at hi h static magnetic fields (B-0) severely impairs image quality. To overcome this effect in brain T-1-weighted images the, MPRAGE sequence was modified to generate two different images at different inversion times MP2RAGE By combining the two images in a novel fashion, it was possible to create T-1-weigthed images where the result image was free of proton density contrast, T-2* contrast, reception bias field, and, to first order transmit field inhomogeneity. MP2RAGE sequence parameters were optimized using Bloch equations to maximize contrast-to-noise ratio per unit of time between brain tissues and minimize the effect of B-1(+) variations through space. Images of high anatomical quality and excellent brain tissue differentiation suitable for applications such as segmentation and voxel-based morphometry were obtained at 3 and 7 T. From such T-1-weighted images, acquired within 12 min, high-resolution 3D T-1 maps were routinely calculated at 7 T with sub-millimeter voxel resolution (0.65-0.85 mm isotropic). T-1 maps were validated in phantom experiments. In humans, the T, values obtained at 7 T were 1.15 +/- 0.06 s for white matter (WM) and 1.92 +/- 0.16 s for grey matter (GM), in good agreement with literature values obtained at lower spatial resolution. At 3 T, where whole-brain acquisitions with 1 mm isotropic voxels were acquired in 8 min the T-1 values obtained (0.81 +/- 0.03 S for WM and 1.35 +/- 0.05 for GM) were once again found to be in very good agreement with values in the literature. (C) 2009 Elsevier Inc. All rights reserved.

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NICaN Regional Supportive & Palliative Care Network Friday 30th May 2008 Lecture Theatre, Fern House Antrim 2.00 pm - 5.00 pm Welcome, Introductions Stuart MacDonnell, Chair of the Supportive and Palliative Care network welcomed everyone to the meeting. This meeting had been rescheduled to accommodate the validation workshop for the regional palliative care model, which took place on Friday,18th April. Acknowledging the full agenda, several items were pulled forward to accommodate speakers SPC_0809_03 Modernisation and Reform of Supportive and Palliative care Mr MacDonnell welcomed Dr Sonja McIlfatrick and Dr Donna Fitzimons, members of the Phase 1 Project Team for the Modernisation and Reform of palliative care. Their presentation highlighted the journey taken by the Project Team since January 2008 - May 2008. Seeking to deliver the network vision, for any person with palliative care need, cancer or non - cancer, the project team incorporated several methodologies. The literature review identified best practice. An assessment of need including epidemiological data and review of service provision. Consultation reflected the engagement with patients, carers and professional forums, primary care and non-malignant focus groups. The breadth of consultation confirmed the evidence for the identified components of the model. These were validated at the April workshop. External review of the work was provided by Dr Phil Larkin (Galway Uni) Prof David Clark (End of Life Care Observatory, Lancaster University) and Mr Bob Neillans (Chair of the Mid Trent Palliative care network, which has been involved in the Delivering choice programme within Lincolnshire). The Guiding Principles of the model reinforced Patient and family centred care, enhanced community provision and supported by specialists. The components of the model are · Identification of patient with Palliative careened · Holistic Assessment · Integration of services · Coordination of care · End of Life Care and Bereavement Care The consultation process also highlighted the need for Increased Public and Professional Awareness. This was recognised as an encompassing component. Underpinning the model is the need for robust Education and common core values e.g. dignity, choice, advocacy, empowerment, partnership working. Stuart MacDonnell, who also chaired the steering group during the project, congratulated the Project Team for delivering the comprehensive document on schedule. The Report has been submitted to the NICaN Board and the DHSSPSNI. In addition, an outline for Phase 2 of this work has been submitted. Mr MacDonnell recognised that there is real opportunity for palliative care to benefit from the DHSSPSNI commitment to concrete developments. Phase 2 will progress the current high-level components of the model into quality services developments at a local level, demonstrating integration throughout. The methods propose continued engagement with the Delivering Choice Programme enabled through a Central and also Local Teams. The report and the Appendices care available on the NICaN website www.nican@n-i.nhs.uk SPC_0809_01 Chairman's Business · Update on the Cancer Service Framework, the document has been submitted and presented to the Departmental Programme Board. Next stages will include the review of costs and development of a implementation guidance It is hoped that the completed document should be available for public consultation in Autumn 2008. with a launch of the framework document and accompanying implementation guide in Spring 2009. Some funding has already been identified to advance key areas of work including, Advanced communication skills training, peer review and an appointment of a post to develop the cancerni.net, focusing on children and e-learning tools. · Children's and Adolescent Cancer network group , Liz Henderson is to convene a group to consider how this is to be taken forward. · NICaN appointments Recognition was given to the significant contribution made by Dr Gerard Daly during his position as NICaN Lead Clinician, particularly throughout the early establishment of the NICaN. Dr Dermott Hughes (Western Trust) has been appointed as the NICaN Medical Director. The Primary Care Director post has been advertised and it is hoped that the Director of Network will be advertised later in Summer. Endorsement of End of Life care paper. The Paper was presented and endorsed at the March 2008 NICaN Board meeting. Mr David Galloway (Director of Secondary Care) emphasised the need for this important work to be recognised within the regional model to ensure that it is reflected in future models of service delivery Congratulations were again echoed to the Chair of the End of Life Group for this work, Dr Glynis Henry, and the working group Other recognition Mr MacDonnell congratulated the significant achievements across the network. These include: · Dr Francis Robinson (Consultant Palliative Medicine, Western Trust) Awarded - Consultant of the year at the NI Health Care awards. · Mrs Evelyn Whittaker Hospice Nurse Specialist, NI Hospice, Joint Second Prize in the Development award within the International Journal of Palliative Nursing Awards, for her work in development of palliative care education in nursing homes. · Mr Ray Elder is the newly appointed Team Leader of Community Palliative care, SE Trust. · Mrs Bridget Denvir, who managed the establishment of one of the first community multiprofessional palliative care teams is moving to work with establishing integrated teams within the Belfast Trust. Bridget has been an active core member of the network and here contribution has been much appreciated. Mrs Sharon Barr will attend in future. SPC_0809_02 Minutes & matters Arising from Meeting, 13th December 2007 No amendments were made to the draft minutes from the December meeting. These will be posted on the NICaN website for future reference. Palliative Care Research Following consultation, the response to the business case for the All Ireland Institute was forwarded on 22 February 2008 to Prof David Clark. Prof Judith Hill informed the group that terms of tender are now being developed. Awareness raising across academic institutions continues to engage interest in potential partnerships. Atlantic Philantrophies have offered financial support to the venture and match funding is being sought from across jurisdictions. Previous discussions at Network meetings have endorsed the need to establish a work strand for research and development within palliative and end of life care. To identify the body of interested parties and explore the strengths and weaknesses of a collaborative model for research, a workshop, - Building collaboration for Palliative and End of life Care Research -will take place on 4 June 10am - 2pm.in the Comfort Hotel.Antrim, The workshop will be chaired by Prof David Clark, Director of the International Observatory on End of Life Care. Prof Shelia Payne, Help the Hospices Chair in Hospice Studies and co director of the Cancer Experiences Collaborative will present the Experiences and Results from Research Collaborative. Feedback from this event will be brought back to the next meeting in September. SPC_0809_04 Patient Information pathways - a pathway for advanced disease Ms Danny Sinclair, NICaN Regional Coordinator for Patient Information informed the network of how patient information pathways have been developed in line with the Cancer Services Collaborative. Emerging themes, with regard to information needs of patients with advanced disease, are being identified from the work undertaken across the tumour groups. It is important to identify all information needs to develop a generic pathway of information resources for advanced disease to be endorsed by the Supportive and Palliative care network. This could be used across the all tumour specific information pathways and across organisational boundaries. The resulting pathway could potentially be used for non- cancer condition. A group is to be established to take this work forward. The group will: · Develop a list of advanced disease information themes · .Identify when they become relevant for the patient or their carer · .Identify existing resources · .Develop resources where needed · .Participate or nominate when review is required Dr Sheila Kelly nominated Helen Hume (SETrust) Paula Kealey will also contribute to this work; a nomination from the Patient and Public Information Forum has also been identified. A date will be circulated across the network to engage further interest and establish group SPC_0809_08 Development of a Regional Syringe Driver Prescription Chart Ms Kathy Stephenson reported that the second consultation of the draft regional syringe driver prescription chart and the focus group discussions, Pilots of the chart are to be undertaken within Trust, Hospices and General Practices. SPC_0809_05 A framework for Generalist and Specialist Palliative and End of Life Care Competency Dr Kathleen Dunne, lead of the Education works strand, reported on the findings following consultation of the Education framework. The report was widely appreciated across the network and valued as a significant and timely document for the commissioning of generalist and specialist adult palliative care education. Mr MacDonnell congratulated Dr Dunne and the members of the education workstrand for developing the framework aligning its significance to the underpinning needs of the regional model Amendments will be made to the document and then forwarded to the NICaN Board for endorsement. A process of implementation will be explored and reported to the network group at the September meeting. Key target areas for generalist palliative care education were highlighted within care of the elderly and general medicine. . SPC_0809_06 Pallcareni.net-a website for people with palliative care needs Ms Danny Sinclair, reminded the group of the pending amalgamation of the CAPriCORN and NICaN website. The resulting new web address will be www. cancerni.net. Recurrent funding has been secured to ensure the development of the supportive and palliative care website.www.Pallcareni.net The new website will host good information for people with palliative care needs, regardless of diagnosis. It will be accessible via the cancerni.net portal or independently as the pallcareni portal. It will signpost people with palliative care needs to condition- specific websites. The website will also enable the communication needs of the NI Regional Supportive & Palliative Care Network. This is a very significant method of seeking to enable greater understanding of palliative care for public and professionals, as highlighted within the regional model. Currently the material from the CAPriCORN website is being migrated onto cancerni and /or pallcareni.net as appropriate. To enable the further development of this opportunity a steering group of interested individuals is to be established. Their role will be to: · Drive the development of the website so it meets the needs of public and professionals through the sourcing and development of additional content · Identify any support that is needed, e.g. technical support · Review the website as a whole as it grows (coordinating condition-specific developments) · Review the functions of the website to aid communication throughout the Supportive and Palliative care network The steering group representation should reflect the constituencies within the Supportive and Palliative Care network. Current expressions of interest have come from Heather Reid and Valerie Peacock. A date will be circulated across the network to engage further interest and establish group SPC_0809_07 Update of Guidelines workstrand Dr Pauline Wilkinson presented the current work within the guidelines workstrand. 1. Brief Holistic Assessment & Referral Criteria to Specialist Palliative Care The development of an Holistic assessment Tool will help to identify holistic need at generalist and specialist level. Recognition of complex need prompts appropriate referral to specialist palliative care. The regional referral form is compatible with the Minimum Data set. The final drafts of this work are to be circulated widely, inclusive of service framework groups, primary care, secondary care and the supportive and palliative care network. Consultation will take place during June and July. Piloting of the forms will also be undertaken. 2. Control of Pain in Cancer Patients The original guidelines where developed 2003 and are now ready for review. The Mapping exercise, undertaken in May 2007, highlighted that the Guidelines were poorly adopted. The group have reviewed the pending SIGN 2 guidelines for pain with regard to practice in Northern Ireland. These are highly evidence based and are due to be launched this Summer. Whilst an excellent resource their comprehensiveness limits their readability, this may result in poor compliance. The Guidelines group feel it is important to have accessible and user-friendly guidelines particularly for Generalists and Out of hours. There are examples of good work that has taken place across the province, but there is a need for regional consistency. Dr Wilkinson has contacted Dr Carolyn Harper (Deputy CMO) and GAIN with regard to enabling funding to progress this work. The Guidelines group hope to approach the NICaN Primary Care Group to work in collaboratively on this piece, based on the templates already available. The works should be available in both electronic and paper versions. 3. Care of the dying & Breaking bad news Dr Gail Johnston has now completed an Audit of the Care of the Dying Pathways within the EHSSB. Gail is also seeking to examine to what extent the Regional Guidelines for Breaking Bad News are being implemented in the EHSSB with a view to identifying the need for further training or organisational structures that would facilitate future uptake. 4. Advances in new Technology Syringe Drivers Dr Wilkinson reported on a presentation made to the guidelines group by Mr Jim Elliot, Principle Engineer, Cardiology & Ann McLean, and Macmillan Palliative Care Nurse RVH. There is increasing concern with regard to how devices meet the recommended safety standards and how to reduce error. New devices have 3 point checking, automatic detection of syringe, automatic flow rates, full range of alarms, battery status and data download to provide an event log. There are now 2 companies in UK who have devices that meet these safety criteria. The current Graseby syringe drivers, which have been on the market and used predominately within Northern Ireland over the past 27 years Most new devices are not compatible with the regionally available monoject syringe, however contractual changes will lead to the withdrawal of the monoject syringes in October 2008. The Guidelines group supports a regional approach to this matter. This was echoed in the Supportive and Palliative care network. An option appraisal, identifying costs, and training issues should be developed through the engagement with Trusts and DHSSPSNI. The issue of Patient safety should be raised with the DHSSPSNI. SPC_0809_09 Evaluation of Supportive and Palliative Care network Deferred to next meeting. . SPC_0809_10 Emerging Issues Mrs Anne Coyle, Bereavement Coordinator, Southern Trust, announced that the Regional Bereavement Strategy is soon to be released. Anne supported the close alignment between the content of the strategy and the work of the regional model and other workstrands within the Supportive and Palliative care network. Ms Eleanor Donaghy, Transplant Coordinator, briefly highlighted the issue of tissue donation. Each year Northern Ireland has a dearth of corneal donations. There is no upper age limit for donation and retrieval is not limited by a cancer diagnosis. Recipients do not require immunosuppressive and the transplant is lifelong. The National Blood Service provided coordination of this donation they may be contacted via 07659180773. It is hoped that Mrs Coyle and Ms Donaghy could provide more comprehensive presentations at a future meeting. Events · Irish Psycho- Oncology Group Seminar, Cork 6 June, Exploring the Struggle for meaning in Cancer · Integrated Care: Putting Research into Practice, 13June, Trinity College, Dublin · Macmillan online conference Friday 13 June 2008, 9am - 5pm · Delivering effective end of life care: developing partnership working 15 Oct 2008, 9.30 -4.15 pm London Network Meeting was closed at 5.00pm SPC_0607_ Dates of Future Meetings (please note the change of venue) 10th September 2008, 1.30 - 5pm venue to be decided15th January 2009, 1.30 - 5pm venue to be decided12th May 2009, 1.30 - 5pm venue to be decided Attendances Apologies Stuart MacDonnellLorna NevinSonja McIlfatrick Donna FitzsimonsKathleen DunnePauline WilkinsonKathy StephensonSheila KellyMarie Nugent,Anne CoyleFiona GilmourJudith HillLorna DicksonMargaret CarlinLoretta GribbenYvonne Duff Lesley NelsonLiz HendersonSue FosterCathy PayneGraeme PaynePatricia MageeGeraldine WeatherupPaula KealyCaroline McAfeeLinda WrayValerie PeacockAnn McCleanRay Elder Martin BradleyHelen HumeGillian RankinHeather MonteverdeJulie DoyleAlison PorterYvonne SmythLiz Atkinson,Glynis HenryMaeve HullyCaroline HughesAnn FinnBob BrownSharon BarrJulie DoyleJanis McCulla .

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BACKGROUND: Two long synthetic peptides representing the dimorphic and constant C-terminal domains of the two allelic families of Plasmodium falciparum merozoite surface proteins 2 are considered promising malaria vaccine candidates. The aim of the current study is to characterize the immune response (epitope mapping) in naturally exposed individuals and relate immune responses to the risk of clinical malaria. METHODS: To optimize their construction, the fine specificity of human serum antibodies from donors of different age, sex and living in four distinct endemic regions was determined in ELISA by using overlapping 20 mer peptides covering the two domains. Immune purified antibodies were used in Western blot and immunofluorescence assay to recognize native parasite derivate proteins. RESULTS: Immunodominant epitopes were characterized, and their distribution was similar irrespective of geographic origin, age group and gender. Acquisition of a 3D7 family and constant region-specific immune response and antibody avidity maturation occur early in life while a longer period is needed for the corresponding FC27 family response. In addition, the antibody response to individual epitopes within the 3D7 family-specific region contributes to protection from malaria infection with different statistical weight. It is also illustrated that affinity-purified antibodies against the dimorphic or constant regions recognized homologous and heterologous parasites in immunofluorescence and homologous and heterologous MSP2 and other polypeptides in Western blot. CONCLUSION: Data from this current study may contribute to a development of MSP2 vaccine candidates based on conserved and dimorphic regions thus bypassing the complexity of vaccine development related to the polymorphism of full-length MSP2.

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The trabecular bone score (TBS) is a gray-level textural metric that can be extracted from the two-dimensional lumbar spine dual-energy X-ray absorptiometry (DXA) image. TBS is related to bone microarchitecture and provides skeletal information that is not captured from the standard bone mineral density (BMD) measurement. Based on experimental variograms of the projected DXA image, TBS has the potential to discern differences between DXA scans that show similar BMD measurements. An elevated TBS value correlates with better skeletal microstructure; a low TBS value correlates with weaker skeletal microstructure. Lumbar spine TBS has been evaluated in cross-sectional and longitudinal studies. The following conclusions are based upon publications reviewed in this article: 1) TBS gives lower values in postmenopausal women and in men with previous fragility fractures than their nonfractured counterparts; 2) TBS is complementary to data available by lumbar spine DXA measurements; 3) TBS results are lower in women who have sustained a fragility fracture but in whom DXA does not indicate osteoporosis or even osteopenia; 4) TBS predicts fracture risk as well as lumbar spine BMD measurements in postmenopausal women; 5) efficacious therapies for osteoporosis differ in the extent to which they influence the TBS; 6) TBS is associated with fracture risk in individuals with conditions related to reduced bone mass or bone quality. Based on these data, lumbar spine TBS holds promise as an emerging technology that could well become a valuable clinical tool in the diagnosis of osteoporosis and in fracture risk assessment. © 2014 American Society for Bone and Mineral Research.

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The quantity of interest for high-energy photon beam therapy recommended by most dosimetric protocols is the absorbed dose to water. Thus, ionization chambers are calibrated in absorbed dose to water, which is the same quantity as what is calculated by most treatment planning systems (TPS). However, when measurements are performed in a low-density medium, the presence of the ionization chamber generates a perturbation at the level of the secondary particle range. Therefore, the measured quantity is close to the absorbed dose to a volume of water equivalent to the chamber volume. This quantity is not equivalent to the dose calculated by a TPS, which is the absorbed dose to an infinitesimally small volume of water. This phenomenon can lead to an overestimation of the absorbed dose measured with an ionization chamber of up to 40% in extreme cases. In this paper, we propose a method to calculate correction factors based on the Monte Carlo simulations. These correction factors are obtained by the ratio of the absorbed dose to water in a low-density medium □D(w,Q,V1)(low) averaged over a scoring volume V₁ for a geometry where V₁ is filled with the low-density medium and the absorbed dose to water □D(w,QV2)(low) averaged over a volume V₂ for a geometry where V₂ is filled with water. In the Monte Carlo simulations, □D(w,QV2)(low) is obtained by replacing the volume of the ionization chamber by an equivalent volume of water, according to the definition of the absorbed dose to water. The method is validated in two different configurations which allowed us to study the behavior of this correction factor as a function of depth in phantom, photon beam energy, phantom density and field size.

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Vaccines have had an unquestionable impact on public health during the last century. The most likely reason for the success of vaccines is the robust protective properties of specific antibodies. However, antibodies exert a strong selective pressure and many microorganisms, such as the obligatory intracellular parasite Trypanosoma cruzi, have been selected to survive in their presence. Although the host develops a strong immune response to T. cruzi, they do not clear the infection and instead progress to the chronic phase of the disease. Parasite persistence during the chronic phase of infection is now considered the main factor contributing to the chronic symptoms of the disease. Based on this finding, containment of parasite growth and survival may be one method to avoid the immunopathology of the chronic phase. In this context, vaccinologists have looked over the past 20 years for other immune effector mechanisms that could eliminate these antibody-resistant pathogens. We and others have tested the hypothesis that non-antibody-mediated cellular immune responses (CD4+ Th1 and CD8+ Tc1 cells) to specific parasite antigens/genes expressed by T. cruzi could indeed be used for the purpose of vaccination. This hypothesis was confirmed in different mouse models, indicating a possible path for vaccine development.

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MRI visualization of devices is traditionally based on signal loss due to T(2)* effects originating from local susceptibility differences. To visualize nitinol devices with positive contrast, a recently introduced postprocessing method is adapted to map the induced susceptibility gradients. This method operates on regular gradient-echo MR images and maps the shift in k-space in a (small) neighborhood of every voxel by Fourier analysis followed by a center-of-mass calculation. The quantitative map of the local shifts generates the positive contrast image of the devices, while areas without susceptibility gradients render a background with noise only. The positive signal response of this method depends only on the choice of the voxel neighborhood size. The properties of the method are explained and the visualizations of a nitinol wire and two stents are shown for illustration.

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A recent trend in digital mammography is computer-aided diagnosis systems, which are computerised tools designed to assist radiologists. Most of these systems are used for the automatic detection of abnormalities. However, recent studies have shown that their sensitivity is significantly decreased as the density of the breast increases. This dependence is method specific. In this paper we propose a new approach to the classification of mammographic images according to their breast parenchymal density. Our classification uses information extracted from segmentation results and is based on the underlying breast tissue texture. Classification performance was based on a large set of digitised mammograms. Evaluation involves different classifiers and uses a leave-one-out methodology. Results demonstrate the feasibility of estimating breast density using image processing and analysis techniques

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The sandfly Phlebotomus perniciosus is the most widespread vector of Leishmania infantum in Spain. Laboratory colonisation represents the most feasible source of information on the biology of these insects, but in conducting any study, the density of individuals in the colony may drop to such an extent that it is sometimes difficult to recover the initial population levels. A new technique was tested for the recovery of sandfly eggs in three different colonies; the recovery rate was studied by comparing the standard method of mass rearing with this new method of colony management. The results demonstrate a mean increase of 18.4% in adult production, a growth in colony productivity that justifies the inclusion of this process in the routine maintenance of any colony of sandflies.

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The need for drug combinations to treat visceral leishmaniasis (VL) arose because of resistance to antimonials, the toxicity of current treatments and the length of the course of therapy. Calcium channel blockers (CCBs) have shown anti-leishmanial activity; therefore their use in combination with standard drugs could provide new alternatives for the treatment of VL. In this work, in vitro isobolograms of Leishmania (Leishmania) chagasi using promastigotes or intracellular amastigotes were utilised to identify the interactions between five CCBs and the standard drugs pentamidine, amphotericin B and glucantime. The drug interactions were assessed with a fixed ratio isobologram method and the fractional inhibitory concentrations (FICs), sum of FICs (ΣFICs) and the overall mean ΣFIC were calculated for each combination. Graphical isobologram analysis showed that the combination of nimodipine and glucantime was the most promising in amastigotes with an overall mean ΣFIC value of 0.79. Interactions between CCBs and the anti-leishmanial drugs were classified as indifferent according to the overall mean ΣFIC and the isobologram graphic analysis.

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BACKGROUND AND OBJECTIVE: In bladder cancer, conventional white light endoscopic examination of the bladder does not provide adequate information about the presence of "flat" urothelial lesions such as carcinoma in situ. In the present investigation, we examine a new technique for the photodetection of such lesions by the imaging of protoporphyrin IX (PpIX) fluorescence following topical application of 5-aminolevulinic acid (ALA). STUDY DESIGN/MATERIALS AND METHODS: Several hours after bladder instillation of an aqueous solution of ALA in 34 patients, a Krypton ion laser or a filtered Xenon arc-lamp was used to excite PpIX fluorescence. Tissue samples for histological analysis were taken while observing the bladder wall either by means of a video camera, or by direct endoscopic observation. RESULTS: A good correlation was found between the PpIX fluorescence and the histopathological diagnosis. On a total of 215 biopsies, 143 in fluorescent and 72 in nonfluorescent areas, all visible tumors on white light cytoscopy appeared in a bright red fluorescence with the photodetection technique. In addition, this method permitted to discover 47 unsuspected carcinomatous lesions on white light observation, among which 40% were carcinoma in situ. CONCLUSION: PpIX fluorescence induced by instillation into the bladder of 5-ALA is an efficient method of mapping the mucosa in bladder carcinoma.

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RESUME Les améliorations méthodologiques des dernières décennies ont permis une meilleure compréhension de la motilité gastro-intestinale. Il manque toutefois une méthode qui permette de suivre la progression du chyme le long du tube gastro-intestinal. Pour permettre l'étude de la motilité de tout le tractus digestif humain, une nouvelle technique, peu invasive, a été élaborée au Département de Physiologie, en collaboration avec l'EPFL. Appelée "Magnet Tracking", la technique est basée sur la détection du champ magnétique généré par des matériaux ferromagnétiques avalés. A cet usage, une pilule magnétique, une matrice de capteurs et un logiciel ont été développés. L'objet de ce travail est de démontrer la faisabilité d'un examen de la motilité gastro-intestinale chez l'Homme par cette méthode. L'aimant est un cylindre (ø 6x7 mm, 0.2 cm3) protégé par une gaine de silicone. Le système de mesure est constitué d'une matrice de 4x4 capteurs et d'un ordinateur portable. Les capteurs fonctionnent sur l'effet Hall. Grâce à l'interface informatique, l'évolution de la position de l'aimant est suivie en temps réel à travers tout le tractus digestif. Sa position est exprimée en fonction du temps ou reproduite en 3-D sous forme d'une trajectoire. Différents programmes ont été crées pour analyser la dynamique des mouvements de l'aimant et caractériser la motilité digestive. Dix jeunes volontaires en bonne santé ont participé à l'étude. L'aimant a été avalé après une nuit de jeûne et son séjour intra digestif suivi pendant 2 jours consécutifs. Le temps moyen de mesure était de 34 heures. Chaque sujet a été examiné une fois sauf un qui a répété sept fois l'expérience. Les sujets restaient en décubitus dorsal, tranquilles et pouvaient interrompre la mesure s'ils le désiraient. Ils sont restés à jeûne le premier jour. L'évacuation de l'aimant a été contrôlée chez tous les sujets. Tous les sujets ont bien supporté l'examen. Le marqueur a pu être détecté de l'oesophage au rectum. La trajectoire ainsi constituée représente une conformation de l'anatomie digestive : une bonne superposition de celle-ci à l'anatomie est obtenue à partir des images de radiologie conventionnelle (CT-scan, lavement à la gastrografine). Les mouvements de l'aimant ont été caractérisés selon leur périodicité, leur amplitude ou leur vitesse pour chaque segment du tractus digestif. Ces informations physiologiques sont bien corrélées à celles obtenues par des méthodes établies d'étude de la motilité gastro-intestinale. Ce travail démontre la faisabilité d'un examen de la motilité gastro-intestinal chez l'Homme par la méthode de Magnet Tracking. La technique fournit les données anatomiques et permet d'analyser en temps réel la dynamique des mouvements du tube digestif. Cette méthode peu invasive ouvre d'intéressantes perspectives pour l'étude de motilité dans des conditions physiologiques et pathologiques. Des expériences visant à valider cette approche en tant que méthode clinique sont en voie de réalisation dans plusieurs centres en Suisse et à l'étranger. SUMMARY Methodological improvements realised over the last decades have permitted a better understanding of gastrointestinal motility. Nevertheless, a method allowing a continuous following of lumina' contents is still lacking. In order to study the human digestive tract motility, a new minimally invasive technique was developed at the Department of Physiology in collaboration with Swiss Federal Institute of Technology. The method is based on the detection of magnetic field generated by swallowed ferromagnetic materials. The aim of our work was to demonstrate the feasibility of this new approach to study the human gastrointestinal motility. The magnet used was a cylinder (ø6x7mm, 0.2 cm3) coated with silicon. The magnet tracking system consisted of a 4x4 matrix of sensors based on the Hall effect Signals from the sensors were digitised and sent to a laptop computer for processing and storage. Specific software was conceived to analyse in real time the progression of the magnet through the gastrointestinal tube. Ten young and healthy volunteers were enrolled in the study. After a fasting period of 12 hours, they swallowed the magnet. The pill was then tracked for two consecutive days for 34 hours on average. Each subject was studied once except one who was studied seven times. Every subject laid on his back for the entire experiment but could interrupt it at anytime. Evacuation of the magnet was controlled in all subjects. The examination was well tolerated. The pill could be followed from the esophagus to the rectum. The trajectory of the magnet represented a "mould" of the anatomy of the digestive tube: a good superimposition with radiological anatomy (gastrografin contrast and CT) was obtained. Movements of the magnet were characterized by periodicity, velocity, and amplitude of displacements for every segment of the digestive tract. The physiological information corresponded well to data from current methods of studying gastrointestinal motility. This work demonstrates the feasibility of the new approach in studies of human gastrointestinal motility. The technique allows to correlate in real time the dynamics of digestive movements with the anatomical data. This minimally invasive method is ready for studies of human gastrointestinal motility under physiological as well as pathological conditions. Studies aiming at validation of this new approach as a clinically relevant tool are being realised in several centres in Switzerland and abroad. Abstract: A new minimally invasive technique allowing for anatomical mapping and motility studies along the entire human digestive system is presented. The technique is based on continuous tracking of a small magnet progressing through the digestive tract. The coordinates of the magnet are calculated from signals recorded by 16 magnetic field sensors located over the abdomen. The magnet position, orientation and trajectory are displayed in real time. Ten young healthy volunteers were followed during 34 h. The technique was well tolerated and no complication was encountered, The information obtained was 3-D con-figuration of the digestive tract and dynamics of the magnet displacement (velocity, transit time, length estimation, rhythms). In the same individual, repea-ted examination gave very reproducible results. The anatomical and physiological information obtained corresponded well to data from current methods and imaging. This simple, minimally invasive technique permits examination of the entire digestive tract and is suitable for both research and clinical studies. In combination with other methods, it may represent a useful tool for studies of Cl motility with respect to normal and pathological conditions.

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As the distribution of Candida species and their susceptibility to antifungal agents have changed, a new means of accurately and rapidly identifying these species is necessary for the successful early resolution of infection and the subsequent reduction of morbidity and mortality. The current work aimed to evaluate ribosomal RNA gene sequencing for the identification of medically relevant Candida species in comparison with a standard phenotypic method. Eighteen reference strains (RSs), 69 phenotypically identified isolates and 20 inconclusively identified isolates were examined. Internal transcribed spaces (ITSs) and D1/D2 of the 26S ribosomal RNA gene regions were used as targets for sequencing. Additionally, the sequences of the ITS regions were used to establish evolutionary relationships. The sequencing of the ITS regions was successful for 88% (94/107) of the RS and isolates, whereas 100% of the remaining 12% (13/107) of the samples were successfully analysed by sequencing the D1/D2 region. Similarly, genotypic analysis identified all of the RS and isolates, including the 20 isolates that were not phenotypically identified. Phenotypic analysis, however, misidentified 10% (7/69) of the isolates. Phylogenetic analysis allowed the confirmation of the relationships between evolutionarily close species. Currently, the use of genotypic methods is necessary for the correct identification of Candida species.

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Stenotrophomonas maltophilia is a multidrug-resistant nosocomial pathogen that is difficult to identify unequivocally using current methods. Accordingly, because the presence of this microorganism in a patient may directly determine the antimicrobial treatment, conventional polymerase chain reaction (PCR) and real-time PCR assays targeting 23S rRNA were developed for the specific identification of S. maltophilia. The PCR protocol showed high specificity when tested against other species of Stenotrophomonas, non-fermentative Gram-negative bacilli and 100 clinical isolates of S. maltophilia previously identified using the Vitek system.