951 resultados para Calculated (de Bruyn et al. 2009)


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The first Australian palliative care nurse practitioner (NP) was endorsed in 2003. In 2009 the Victoria Department of Health funded the development of the Victorian Palliative Care Nurse Practitioner Collaborative (VPCNPC). Its aim was to promote the NP role, develop resources, and provide education and mentorship to NPs, nurse practitioner candidates (NPCs), and health service managers. Four key objectives were developed: identify the demographic profile of palliative care NPCs in Victoria; develop an education curriculum and practical resources to support the training and education of palliative care NPCs and NPs; provide mentorship to NPs, NPCs, and service managers; and ensure effective communication with all key stakeholders. An NPC survey was also conducted to explore NPC demographics, models of care, the hours of study required for the role, the mentoring process, and education needs. This paper reports on the establishment of the VPCNPC, the steps taken to achieve its objectives, and the results of the survey. The NP role in palliative care in Australia continues to evolve, and the VPCNPC provides a structure and resources to clearly articulate the benefits of the role to nursing and clinical services. The advanced clinical practice role of the nurse practitioner (NP) has been well established in North America for several decades and across a range of specialties (Ryan-Woolley et al, 2007; Poghosyan et al, 2012). The NP role in Australia and the UK is a relatively new initiative that commenced in the early 2000s (Gardner et al, 2009). There are over 1000 NPs across all states and territories of Australia, of whom approximately 130 work in the state of Victoria (Victorian Government Health Information, 2012). Australian NPs work across a range of specialties, including palliative, emergency, older person, renal, cardiac, respiratory, and mental health care. There has been increasing focus nationally and internationally on developing academic programmes specifically for nurses working toward NP status (Gardner et al, 2006). There has been less emphasis on identifying the comprehensive clinical support requirements for NPs and NP candidates (NPCs) to ensure they meet all registration requirements to achieve and/or maintain endorsement, or on articulating the ongoing requirements for NPs once endorsed. Historically in Australia there has been a lack of clarity and limited published evidence on the benefits of the NP role for patients, carers, and health services (Quaglietti et al, 2004; Gardner and Gardner, 2005; Bookbinder et al, 2011; Dyar et al, 2012). An NP is considered to be at the apex of clinical nursing practice. The NP role typically entails comprehensively assessing and managing patients, prescribing medicines, making direct referrals to other specialists and services, and ordering diagnostic investigations (Australian Nursing and Midwifery Council, 2009). All NPs in Australia are required to meet the following generic criteria: be a registered nurse, have completed a Nursing and Midwifery Board of Australia approved postgraduate university Master's (nurse practitioner) degree programme, and be able to demonstrate a minimum of 3 years' experience in an advanced practice role (Nursing and Midwifery Board of Australia, 2011). An NPC in Victoria is a registered nurse employed by a service or organisation to work toward meeting the academic and clinical requirements for national endorsement as an NP. During the period of candidacy, which is of variable duration, NPCs consolidate their competence to work at the advanced practice level of an NP. The candidacy period is a process of learning the new role while engaging with mentors (medical and nursing) and accessing other learning opportunities both within and outside one's organisation to meet the educational requirements. Integral to the NP role is the development of a model of care that is responsive to identified service delivery gaps that can be addressed by the skills, knowledge, and expertise of an NP. These are unique to each individual service. The practice of an Australian NP is guided by national standards (Nursing and Midwifery Board of Australia 2014). It is defined by four overarching standards: clinical, education, research, and leadership. Following the initial endorsement of four Victorian palliative care NPs in 2005, there was a lull in recruitment. The Victoria Department of Health (DH) recognised the potential benefits of NPs for health services, and in 2008 it provided funding for Victorian public health services to scope palliative care NP models of care that could enhance service delivery and patient outcomes. The scoping strategy was effective and led to the appointment of 16 palliative care nurses to NPC positions over the ensuing 3 years. The NPCs work across a broad range of care settings, including inpatient, community, and outpatient in metropolitan, regional, and rural areas of Victoria. At the same time, the DH also funded the Centre for Palliative Care to establish the Victorian Palliative Care Nurse Practitioner Collaborative (VPCNPC) to support the NPs and NPCs. The Centre is a state-wide service that is part of St Vincent's Hospital Melbourne and a collaborative Centre of the University of Melbourne. Its primary function is to provide training and conduct research in palliative care. The purpose of the VPCNPC was to provide support and mentorship and develop resources targeted at palliative care NPs, NPCs, and health service managers. Membership of the VPCNPC is open to all NPs, NPCs, health service managers, and nurses interested in the NP role. The aim of this paper is to describe the development of the VPCNPC, its actions, and the outcomes of these actions.

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Context: Near-Earth asteroid-comet transition object 107P/ (4015) Wilson-Harrington is a possible target of the joint European Space Agency (ESA) and Japanese Aerospace Exploration Agency (JAXA) Marco Polo sample return mission. Physical studies of this object are relevant to this mission, and also to understanding its asteroidal or cometary nature. Aims: Our aim is to obtain significant new constraints on the surface thermal properties of this object. Methods: We present mid-infrared photometry in two filters (16 and 22 μm) obtained with NASA's Spitzer Space Telescope on February 12, 2007, and results from the application of the Near Earth Asteroid Thermal Model (NEATM). We obtained high S/N in two mid-IR bands allowing accurate measurements of its thermal emission. Results: We obtain a well constrained beaming parameter (η = 1.39±0.26) and obtain a diameter and geometric albedo of D = 3.46±0.32 km, and pV = 0.059±0.011. We also obtain similar results when we apply this best-fitting thermal model to single-band mid-IR photometry reported by Campins et al. (1995, P&SS, 43, 733), Kraemer et al. (2005, AJ, 130, 2363) and Reach et al. (2007, Icarus, 191, 298). Conclusions: The albedo of 4015 Wilson-Harrington is low, consistent with those of comet nuclei and primitive C-, P-, D-type asteorids. We establish a rough lower limit for the thermal inertia of W-H of 60 Jm-2s-0.5 K-1 when it is at r = 1 AU, which is slightly over the limit of 30 Jm-2 s-0.5 K-1 derived by Groussin et al. (2009, Icarus, 199, 568) for the thermal inertia of the nucleus of comet 22P/Kopff.

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There is an increasing recognition of the need to improve inter professional relationships within clinical practice (DoH, 2001). Evidence supports the assertion that health care professionals who are able to communicate and work effectively together and who have a mutual respect and understanding for one another’s roles will provide a higher standard of care (McPherson et al, 2001; Begley, 2008). Providing inter professional education within a University setting offers an opportunity for a non-threatening learning environment where students can develop confidence and build collaborative working relationships with one another (Saxell et al, 2009).
An inter-professional education initiative was developed in Queen’s University Belfast within the Schools of Nursing and Midwifery and Medicine and piloted in 2014. The aim of the collaboration was to introduce concepts of normal labour and birth to fourth year medical students prior to their obstetric and gynaecological placement in hospital. The teaching staff felt this would be an excellent opportunity for final year pre-registration midwifery students to demonstrate their knowledge and understanding on normality in labour and birth by preparing interactive workshops with the medical students. The midwifery students were provided with an outline agenda in relation to content for the workshop, but then were allowed creative licence with regard to delivery of the workshop. The workshops consisted of approximately 4 midwifery students to 12 medical students. Resources such as birthing balls, birth mannequins, dolls and pelvises were available to the students to increase interactivity. Significant emphasis was placed upon the importance of relationship building with women in labour and the concept of being ‘with woman’ was core to all elements of teaching. Midwifery students undertook acting roles such as the labouring woman, partner or a midwife role and acted out mini scenarios such as contacting for advice about early labour; positions for labour or positions for birth. Medical students were prompted to vocalise about their feelings towards labour and birth and encouraged to think about their role within the birth setting.
Preliminary evaluations of the workshops have been extremely positive from both the midwifery students and the medical students. The midwifery students have commented on the enjoyable aspects of team working for preparing for the workshop and also the confidence gained from teaching the medical students. The medical students have evaluated the teaching by the midwifery students positively and felt that it lowered their anxiety going into the labour setting. A number of midwifery and medical students have subsequently worked with one another within the practice setting which has been recognised as beneficial. Both Schools have recognised the benefits of this form of inter professional education and have subsequently made a commitment to embed it within each curriculum.

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Stable isotopes (δ13C, δ15N) have been used to document the utilisation of sewage effluent in coastal marine foodwebs in a number of studies (e.g. Rau et al. 1981; Risk et al. 2009; Rogers 1999; 2003). δ13C and, especially, δ15N showed clear differences in the diet of common limpets (Patella vulgata) collected in June 2010 near the untreated sewage outfall at Blackhead, Northern Ireland and a ‘clean’ site nearby. Because sewage contains a significant portion of fossil-fuel derived compounds (Law et al. 2013), 14C measurements enabled us to estimate the contribution of fossil carbon to the effluent and to the foodweb and hence of the level of sewage contamination. The effluent was found to contain 12.2 ± x % fossil carbon on the day sampled. The modern marine carbon endmember is enriched by the discharge from the Sellafield nuclear fuel reprocessing plant across the Irish Sea (c.f. Cook et al. 2004) so 14C analyses of samples from the ‘clean’ site were needed. We found that 38.5 ±x % of the diet of common limpets collected near the sewage was derived from fossil fuel. We plan to collect samples from the same two sites in June 2014 to establish whether the 2012 relocation of the outfall, with preliminary treated discharge farther out to sea has eliminated the contamination at Blackhead

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There is an increasing recognition of the need to improve interprofessional relationships within clinical practice (Midwifery 2020, 2010). Evidence supports the assertion that healthcare professionals who are able to communicate and work effectively together and who have a mutual respect and understanding for one another’s roles will provide a higher standard of care (McPherson et al, 2001; Miers et al, 2005; Begley, 2008). The joint Royal College of Obstetrics & Gynaecologists(RCOG) / Royal College of Midwives (RCM) report (2008 Page 8) on clinical learning environment and recruitment recommended that “Inter-professional learning strategies should be introduced and supported at an early stage in the medical and midwifery undergraduate students' experience and continued throughout training.” Providing interprofessional education within a University setting offers an opportunity for a non-threatening learning environment where students can develop confidence and build collaborative working relationships with one another (Saxell et al, 2009).Further research supports the influence of effective team working on increased client satisfaction. Additionally it identifies that the integration of interprofessional learning into a curriculum improves students’ abilities to interact professionally and provides a better understanding of role identification within the workplace than students who have only been exposed to uniprofessional education (Meterko et al, 2004; Pollard and Miers, 2008; Siassakos, et al, 2009; Wilhelmsson et al, 2011; Murray-Davis et al, 2012). An interprofessional education indicative has been developed by teaching staff from the School of Nursing and Midwifery and School of Medicine at Queen’s University Belfast. The aim of the collaboration was to enhance interprofessional learning by providing an opportunity for medical students and midwifery students to interact and communicate prior to medical students undertaking their obstetrics and gynaecology placements. This has improved medical students placement experience by facilitating them to learn about the process of birth and familiarisation of the delivery suite environment and it also has the potential to enhance interprofessional relationships. Midwifery students benefit through the provision of an opportunity to teach and facilitate learning in relation to normal labour and birth and has provided them with an opportunity to build stronger and more positive relationships with another profession. This opportunity also provides a positive, confidence building forum where midwifery students utilise teaching and learning strategies which would be transferable to their professional role as registered midwives. The midwifery students were provided with an outline agenda in relation to content for the workshop, but then were allowed creative licence with regard to delivery of the workshop. The interactive workshops are undertaken within the University’s clinical education centre, utilising low fidelity simulation. The sessions are delivered 6 times per year and precede the medical students’ obstetric/gynaecology placement. All 4th year medical and final year midwifery students have an opportunity to participate. Preliminary evaluations of the workshops have been positive from both midwifery and medical students. The teaching sessions provided both midwifery and medical students with an introduction to inter professional learning and gave them an opportunity to learn about and respect each other’s roles. The midwifery students have commented on the enjoyable aspects of team working for preparing for the workshop and also the confidence gained from teaching medical students. The medical students have evaluated the teaching by midwifery students positively and felt that it lowered their anxiety levels going into the labour setting. A number of midwifery and medical students have subsequently worked with one another within the practice setting which has been recognised as beneficial. Both Schools have recognised the benefits of interprofessional education and have subsequently made a commitment to embed it within each curriculum.

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Nearly 4000 people died in Northern Ireland’s long running conflict, 314 of them police officers (Brewer and Magee 1991, Brewer 1996, Hennessey 1999, Guelke and Milton-Edwards 2000). The republican and loyalist ceasefires of 1994 were the first significant signal that NI society was moving beyond the ‘troubles’ and towards a normalised political environment. The Belfast (Good Friday) Agreement of 1998 cemented that movement (Hennessey 1999). Policing was a key and seemingly unresolvable element of the conflict, seen as unrepresentative and partisan. Its reform or ‘recasting’ in a new dispensation was an integral part of the conflict transformation endeavour(Ellison 2010). As one of the most controversial elements of the conflicted past, it had remained outside the Agreement and was subject to a specific commission of interest (1999), generally known as the Patten Commission. The Commission’s far reaching proposals included a change of name, badge and uniform, the introduction of 50/50 recruitment (50% Roman Catholic and 50% other), a new focus on human rights, a new district command and headquarter structure, a review of ‘Special Branch’ and covert techniques, a concern for ‘policing with the community’ and a significant voluntary severance process to make room for new recruits, unconnected with the past history of the organisation(Murphy 2013).

This paper reflects upon the first data collection phase of a long term processual study of organisational change within the Royal Ulster Constabulary / Police Service of Northern Ireland. This phase (1996-2002) covers early organisational change initiation (including the pre-change period) and implementation including the instigation of symbolic changes (name, badge, and crest) and structural changes (new HQ structure and District Command structure). It utilises internal documentation including messages from the organisations leaders, interviews with forty key informants (identified through a combination of snow-balling from referrals by initial contacts, and key interviews with significant individuals), as well as external documentation and commentary on public perceptions of the change. Using a processual lens (Langley, Smallman et al. 2013) it seeks to understand this initial change phase and its relative success in a highly politicised environment.

By engaging key individuals internally and externally, setting up a dedicated change team, adopting a non normative, non urgent, calming approach to dissent, communicating in orthodox and unorthodox ways with members, acknowledging the huge emotional strain of letting go of the organisation’s name and all it embodied, and re-emphasising the role of officers as ‘police first’, rather than ‘RUC first’, the organisations leadership remained in control of a volatile and unhappy organisational body and succeeded in moving it on through this initial phase, even while much of the political establishment lambasted them externally. Three years into this change process the organisation had a new name, a new crest, new structures, procedures and was deeply engaged in embedding the joint principles of human rights and community policing within its re-woven fabric. While significant problems remained, the new Police Service of Northern Ireland had successfully begun a long journey to full community acceptance in a post conflict context.

This case illustrates the significant challenges of leading change under political pressure, with external oversight and no space for failure(Hannah, Uhl-Bien et al. 2009). It empirically reflects the reality of change implementation as messy, disruptive and unpredictable and highlights the significance of political skill and contextual understanding to success in the early stages(Buchanan and Boddy 1992). The implications of this for change theory and the practice of change implementation are explored (Eisenhardt and Graebner 2007) and some conclusions drawn about what such an extreme case tells us about change generally and change implementation under pressure.

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For those working in the humanitarian sector, achieving positive outcomes for postdisaster communities through reconstruction projects is a pressing concern. In the wake of recent natural disasters, NGOs have become increasingly involved in the permanent reconstruction of affected communities. They have encountered significant barriers as they implement reconstruction programmes and this paper argues that it is important to address the visible lack of innovation that is partially to blame. The theoretical bedrock of a current research project will be used as the starting point for this argument, the overall goal of which is to design a competency-based framework model that can be used by NGOs in post-disaster reconstruction projects. Drawing on established theories of management, a unique perspective has been developed from which a competency-based reconstruction theory emerges. This theoretical framework brings together 3 distinct fields; Disaster Management, Strategic Management and Project Management, each vital<br/>to the success of the model. The objectives of this paper are a) to investigate the role of NGOs in post-disaster reconstruction and establish the current standard of practice b) to determine the extent to which NGOs have the opportunity to contribute to sustainable community development through reconstruction c) to outline the main factors of a theoretical framework first proposed by Von Meding et al. 2009 and d) to identify the innovative measures that can be taken by NGOs to achieve more positive outcomes in their interventions. It is important that NGOs involved in post-disaster reconstruction become familiar with concepts and strategies such as those contained in this paper. Competency-based organizational change on the basis of this theory has the potential to help define the standard of best practice to which future NGO projects might align themselves.

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Without human beings, and human activities, hazards can strike but disasters cannot occur, they are not just natural phenomena but a social event (Van Der Zon, 2005). The rapid demand for reconstruction after disastrous events can result in the impacts of projects not being carefully considered from the outset and the opportunity to improve long-term physical and social community structures being neglected. The events that struck Banda Aceh in 2004 have been described as
a story of ‘two tsunamis’, the first being the natural hazard that struck and the second being the destruction of social structures that occurred as a result of unplanned, unregulated and uncoordinated response (Syukrizal et al, 2009). Measures must be in place to ensure that, while aiming to meet reconstruction
needs as rapidly as possible, the risk of re-occurring disaster impacts are reduced through both the physical structures and the capacity of the community who inhabit them. The paper explores issues facing reconstruction in a post-disaster scenario, drawing on the connections between physical and social reconstruction in order to address long term recovery solutions. It draws on a study of relevant literature and a six week pilot study spent in Haiti exploring the progress of recovery in the Haitian capital and the limitations still restricting reconstruction efforts. The study highlights the need for recovery management strategies that recognise the link between social and physical reconstruction and the significance of community based initiatives that see local residents driving recovery in terms of debris handling and rebuilding. It demonstrates how a community driven approach to physical reconstruction could also address the social impacts of events that, in the case of places such as Haiti, are still dramatically restricting recovery efforts.

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The occurrence of Bursaphelenchus species in the Czech Republic is poorly known, the first report of the genus being made by Kubátová et al. (2000) who reported the association of B. eremus with the hyphomycetous microfungus, Esteya vermicola, and the bark beetle, Scolytus intricatus, collected from Quercus robur, in central Bohemia. To date, four other species have been reported from the country, namely B. fungivorus (Braasch et al., 2002), B. hofmanni (see Braasch, 2001), B. mucronatus (see Braasch, 2001) and B. vallesianus (Gaar et al., 2006). More recently, a survey for Bursaphelenchus species associated with bark- and wood-boring insects in the Czech Republic identified B. pinophilus Brzeski & Baujard, 1997 from the Moravia region. Although this represents a new country record, it was also associated with nematangia on the hind wings of a new insect vector. A total of 404 bark- and wood-boring insects were collected from declining or symptomatic trees and screened for the presence of Bursaphelenchus. Bark and longhorn beetles were captured manually after debarking parts of the trunk displaying symptoms of insect attacks. Longhorn beetle larvae were also collected together with logs cut from the trunk. Logs were kept at room temperature in the laboratory until insect emergence. Each adult insect was individually dissected in water and examined for nematodes. All nematodes resembling dauer juveniles of Bursaphelenchus were collected and identified by molecular characterisation using a region of ribosomal DNA (rDNA) containing the internal transcribed spacer regions ITS1 and ITS2. ITS-RFLP analyses using five restriction enzymes (AluI, HaeIII, HinfI, MspI, RsaI) were performed to generate the species-specific profile according to Burgermeister et al. (2009). Species identification was also confirmed by morphological data after culture of the dauers on Botrytis cinerea Pers. ex Ft., growing in 5% malt extract agar. During this survey, only species belonging to the Curculionidae, subfamily Scolytinae, revealed the presence of nematodes belonging to Bursaphelenchus. Dauers of this genus were found aggregated under the elytra in nematangia formed at the root of the hind wings (Fig. 1). The dauers were identified from 12 individuals of Pityogenes bidentatus (Herbst, 1783) (Coleoptera: Scolytinae) collected under the bark of Pinus sylvestris trunks. Each insect carried ca 10-100 dauers. The ITS-RFLP patterns of the dauers so obtained confirmed the identification of B. pinophilus associated with this insect species. Bursaphelenchus pinophilus has been found mainly in Europe and has been reported from various countries such as Poland (Brzeski & Baujard, 1997), Germany (Braasch, 2001), and Portugal (Penas et al., 2007). The recent detection of this species associated with dead P. koraiensis in Korea (Han et al., 2009) expands its geographical distribution and potential importance. It has been found associated only with Pinus species, but very little is known about the insect vector. The bark beetle, Hylurgus ligniperda, was initially suggested as the insect vector by Pe-nas et al. (2006), although the nematode associated with this insect was later reclassified as B. sexdentati by morphological and molecular analysis (Penas et al., 2007). According to the literature, P. bidentatus has been cited as a vector of Ektaphelenchus sp. (Kakuliya, 1966) in Georgia, and an unidentified nematode species in Spain (Roberston et al., 2008). Interestingly, B. pinophilus was found in the nematangia formed at the root of the hind wings of P. bidentatus. Although this phenomenon is not so common in other Bursaphelenchus species, B. rufipennis has been found recently in such a structure on the hind wings of the insect Dendroctonus rufipennis (Kanzaki et al., 2008). Although other nematode species (e.g., Ektaphelenchus spp.) are frequently found associated within the same nematangia (see Kanzaki et al., 2008), in this particular case, only dauers of B. pinophilus were identified. The association between B. pinophilus and P. bidentatus represents the first report of this biological association and the association with the Scolytinae strengthens the tight and specific links between this group of Bursaphelenchus species and members of the Scolytinae (Ryss et al., 2005).

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A compreensão dos estados mentais dos outros – Teoria da Mente (TM) – é um processo crucial no desenvolvimento cognitivo e social. A relação entre a Teoria da Mente e a Linguagem tem sido alvo de vários estudos ao longo das últimas décadas (Happé, 1995; de Villiers & Villiers, 2000; Astington, 2001; Ruffman et al., 2002; Lohmann & Tomasello, 2003; Astington & Baird, 2005; Astington & Pelletier, 2005; Farrar et al, 2009). Neste estudo avaliaram-se 229 crianças entre os 3 e os 7 anos que frequentavam jardim-de-infância. Destas 229 crianças, foram constituídos dois grupos, um constituído por crianças com desenvolvimento típico (GN) e outra por crianças com Perturbações da Fala/ Linguagem (GPFL), sendo que neste último foi ainda criado um sub-grupo de crianças com Perturbações Desenvolvimentais da Linguagem (SGPDL). Foi aplicado um teste de avaliação da TM, constituído por três sub-testes (Compreensão de falsas crenças de primeira ordem, crenças e desejos e acesso ao conhecimento) e um teste de avaliação de linguagem (T.A.L.C.) Foi também pedido aos cuidadores o preenchimento de um Questionário de Avaliação das Competências Sociais (Rydell et al., 1997). Verificou-se a existência de uma associação positiva e significativa entre a idade e a TM. Por outro lado, observou-se a presença de uma associação negativa e significativa entre a idade de início de fala e a TM. De uma forma geral, verifica-se que a TM está associada de forma positiva e estatisticamente significativa com os scores da linguagem, sendo esta relação mais forte relativamente aos aspectos relativos às Intenções comunicativas e score total de Expressão e Compreensão da linguagem. Vimos também que as crianças do SGPDL apresentaram scores inferiores ao nível da TM relativamente ao GN. Encontramos diferenças estatisticamente significativas em relação ao tempo de duração da prova de TM entre o GN e o GPFL, tendo estes últimos necessitado de maior tempo de resposta. Relativamente à associação existente entre competências sociais e TM, verificamos que não se encontrou a existência de correlações estatisticamente significativas, excepto para o factor “Altruísmo”. Pensa-se que este aspecto estará relacionado com o facto das competências de TM avaliadas neste estudo não se encontrarem associadas às questões emocionais, as quais constituem um sub-tipo de TM do tipo afectivo, mas antes do sub-tipo cognitivo. Os indivíduos GN apresentaram valores para a “Orientação Pró-Social, “Iniciação Social e score Total das Competências Sociais significativamente superiores às crianças do GPFL.

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A associação simbiótica de plantas leguminosas com bactérias do género Rhizobium é o maior e mais eficiente contribuinte de azoto fixado biologicamente (Somasegaran e Hoben, 1994; Zahran, 1999). No entanto, o constante aumento da poluição em solos agrícolas, nomeadamente a contaminação por metais devido à aplicação de fertilizantes e de lamas, está a tornar-se um problema ambiental cada vez mais preocupante (Alloway, 1995a; Giller et al., 1998; Permina et al., 2006; Thorsen et al., 2009; Wani et al., 2008), influenciando de forma negativa a persistência destas bactérias nos solos agrícolas, assim como a sua eficácia de nodulação (Broos et al., 2005; Wani et al., 2008;. Zhengwei et al., 2005). Desta forma, o estudo dos mecanismos de tolerância de Rhizobium a metais tornou-se uma área de investigação de elevada importância. Com o trabalho apresentado nesta tese pretendeu-se perceber melhor a tolerância Rhizobium leguminosarum ao cádmio (Cd), dando particular atenção a um mecanismo de tolerância previamente descrito em R. leguminosarum (Lima et al., 2006): a complexação intracelular de Cd pelo tripéptido glutationa (GSH). Assim, o principal objectivo deste trabalho foi perceber melhor qual a importância deste mecanismo nos níveis de tolerância de rizóbio ao Cd. Como já tinha sido descrito em trabalhos anteriores (Figueira et al., 2005; Lima et al., 2006), foi possível verificar que a estirpe mais tolerante ao metal apresenta níveis mais elevados de Cd e GSH intracelulares. Demonstrou-se ainda que a tolerância ao Cd está dependente da maior eficiência no mecanismo de complexação observada na estirpe tolerante, logo durante as primeiras 12 h de crescimento. Gomes et al. (2002) verificou que a acumulação de complexos GSH-Cd no citoplasma inibe a entrada de metal na célula. Como neste trabalho se observou um aumento nos níveis de Cd intracelular na estirpe tolerante ao longo do tempo, surgiu a hipótese dos complexos serem excretados para o espaço periplasmático. Os elevados níveis de GSH e de Cd determinados no espaço periplasmático corroboraram esta hipótese. Neste trabalho demonstrou-se ainda que a eficácia do mecanismo de complexação, depende da actividade enzimática de uma isoforma específica de GST, que apresentou um elevado acréscimo de actividade na presença do metal. Desta forma, os resultados desta tese indicam que, a maior tolerância de R. leguminosarum ao Cd, depende da capacidade das estirpes para induzir a síntese de GSH na presença de Cd e, simultaneamente aumentar a actividade enzimática da GST específica, optimizando assim o mecanismo de complexação de Cd intracelular.

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Dissertação de mestrado, Psicologia Clínica e da Saúde, Faculdade de Ciências Humanas e Sociais, Universidade do Algarve, 2015

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Tese de doutoramento, Ciências Geofísicas e da Geoinformação (Geofisíca), Universidade de Lisboa, Faculdade de Ciências, 2014

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This work describes how genetic programming is applied to evolving controllers for the minimum time swing up and inverted balance tasks of the continuous state and action: limited torque acrobot. The best swing-up controller is able to swing the acrobot up to a position very close to the inverted ‘handstand’ position in a very short time, shorter than that of Coulom (2004), who applied the same constraints on the applied torque values, and to take only slightly longer than the approach by Lai et al. (2009) where far larger torque values were allowed. The best balance controller is able to balance the acrobot in the inverted position when starting from the balance position for the length of time used in the fitness function in all runs; furthermore, 47 out of 50 of the runs evolve controllers able to maintain the balance position for an extended period, an improvement on the balance controllers generated by Dracopoulos and Nichols (2012), which this paper is extended from. The most successful balance controller is also able to balance the acrobot when starting from a small offset from the balance position for this extended period.

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Relatório de Estágio apresentado à Escola Superior de Educação de Lisboa para obtenção de grau de mestre em Ensino do 1.º e 2.º Ciclo do Ensino Básico