858 resultados para post-seminal development


Relevância:

30.00% 30.00%

Publicador:

Resumo:

Juniperus navicularis Gand. is a dioecious endemic conifer that constitutes the understory of seaside pine forests in Portugal, areas currently threatened by increasing urban expansion. The aim of this study is to assess the conservation status of previously known populations of this species located on its core area of distribution. The study was performed in south-west coast of Portugal. Three populations varying in size and pine density were analyzed. Number of individuals, population density, spatial distribution and individual characteristics of junipers were estimated. Female cone, seed characteristics and seed viability were also evaluated. Results suggest that J. navicularis populations are vulnerable because seminal recruitment is scarce, what may lead to a reduction of genetic variability due solely to vegetative propagation. This vulnerability seems to be strongly determined by climatic constraints toward increasing aridity. Ratio between male and female shrubs did not differ from 1:1 in any population. Deviations from 1:1 between mature and non-mature plants were found in all populations, denoting population ageing. Very low seed viability was observed. A major part of described Juniperus navicularis populations have disappeared through direct habitat loss to urban development, loss of fitness in drier and warmer locations and low seed viability. This study is the first to address J. navicularis conservation, and represents a valuable first step toward this species preservation. 

Relevância:

30.00% 30.00%

Publicador:

Resumo:

International migration sets in motion a range of significant transnational processes that connect countries and people. How migration interacts with development and how policies might promote and enhance such interactions have, since the turn of the millennium, gained attention on the international agenda. The recognition that transnational practices connect migrants and their families across sending and receiving societies forms part of this debate. The ways in which policy debate employs and understands transnational family ties nevertheless remain underexplored. This article sets out to discern the understandings of the family in two (often intermingled) debates concerned with transnational interactions: The largely state and policydriven discourse on the potential benefits of migration on economic development, and the largely academic transnational family literature focusing on issues of care and the micro-politics of gender and generation. Emphasizing the relation between diverse migration-development dynamics and specific family positions, we ask whether an analytical point of departure in respective transnational motherhood, fatherhood or childhood is linked to emphasizing certain outcomes. We conclude by sketching important strands of inclusions and exclusions of family matters in policy discourse and suggest ways to better integrate a transnational family perspective in global migration-development policy.

Relevância:

30.00% 30.00%

Publicador:

Resumo:

The paper investigates the dynamics and volution of issues on the agenda of Baltic environmental non-governmental organisations (NGOs) since the collapse of communism. The past research on Baltic environment activism suggests that these enjoy high visibility because they tapped the core societal views of natural environment as a crucial asset of a nation. As we demonstrate in this paper, the changes in agendas of Baltic environmental non-governmental organisations (ENGOs) make clear that the rhetorical toolbox of ‘national environment’ is often used to mainly achieve greater financial gains for individual members, rather than for society at large. We illustrate how the dearth of economic opportunities for domestic public has impacted perceptions of ‘nature’ advocated by the environmental activists, focussing specifically on national perceptions of ownership and the resulting actions appropriating ‘nature’ as a source for economic development, only tangentially attaining environmental outcomes on the way. The vision that the ‘environment’ is an economic resource allowed ENGO activists to cooperate with the domestic policymaking, while tapping international networks and donors for funding. Throughout the past decades they worked to secure their own and their members' particularistic economic interests and, as we demonstrate, remained disengaged from the political process and failed to develop broader reproach with publics.

Relevância:

30.00% 30.00%

Publicador:

Resumo:

Biodiversity loss is a global problem with freshwater bivalves considered amongst the most
endangered biota. The freshwater pearl mussel, Margaritifera margaritifera, is declining
throughout its range owing to habitat degradation and overexploitation. In most of its range,
populations are regarded as reproductively non-functional which has led to the development
of captive breeding programmes. A novel method of releasing M. margaritifera was trialled,
with captive-bred juveniles being released into the rivers caged in ‘mussels silos’ (protective
concrete domes with ventilation creating upwelling to ensure water through flow). We
released 240 juvenile mussels and survival and growth rates were monitored for 18 months
post-release for three size classes: A (13.01-20.00mm); B (10.01-13.00mm); and C (4.01-
10.00mm). We explicitly tested two experimental treatments; one where sediment was added
to each silo (allowing mussels to orientate and burrow) and one without sediment. Survival
by the end of the experiment at month 18 was significantly higher for the largest size class at
97% (though growth was lowest in this cohort), and lowest for the smallest size class at 61%
(though growth was highest in this cohort). Survival and growth were unaffected by the
experimental treatment suggesting that adding sediment offered no advantage. Growth was
positively correlated with both water temperature and the particle size of suspended solids
(both of which were collinear, peaking in summer). There are a large number of ex situ
breeding programmes for freshwater pearl mussels throughout Europe and our finding
suggest that the use of ‘mussel silos’ could be a useful tool to protecting juvenile mussels
allowing them to be released at a relatively early stage of development, minimising the risk of
domestication.

Relevância:

30.00% 30.00%

Publicador:

Resumo:

The paper addresses the development of non-governmental organisations (NGOs) in transition settings. Caught in the balance of knowledge exchange and translation of ideas from abroad, organisations in turbulent setting legitimise their existence by learning through professional networks. By association, organisational actors gain acknowledgement by their sector by traversing the corridors of influence provided by international partnerships. What they learn is how to conduct themselves as agents of change in society, and how to deliver on stated missions and goals, therefore, legitimising their presence in a budding civil society at home. The paper presents a knowledge production and learning practices framework which indicates a presence of dual identity of NGOs - their “embeddedness” locally and internationally. Selected framework dimensions and qualitative case study themes are discussed with respect to the level of independence of organisational actors in the East from their partners in the West in a post-socialist context. A professional global civil society as organisations are increasingly managed in similar, professional ways (Anheier & Themudo 2002). Here knowledge “handling” and knowledge “translation” take place through partnership exchanges fostering capable and/or competitive change-inducing institutions (Czarniawska & Sevon 2005; Hwang & Suarez 2005). How professional identity presents itself in the third sector, as well as the sector’s claim to expertise, need further attention, adding to ongoing discussions on professions in institutional theory (Hwang & Powell 2005; Scott 2008; Noordegraaf 2011). A conceptual framework on the dynamic involved for the construction professional fields follows: • Multiple case analysis provides a taxonomy for understanding what is happening in knowledge transition, adaptation, and organisational learning capacity for NGOs with respect to their role in a networked civil society. With the model we can observe the types of knowledge produced and learning employed by organisations. • There are elements of professionalisation in third sector work organisational activity with respect to its accreditation, sources and routines of learning, knowledge claims, interaction with the statutory sector, recognition in cross-sector partnerships etc. • It signals that there is a dual embeddedness in the development of the sector at the core to the shaping the sector’s professional status. This is instrumental in the NGOs’ goal to gain influence as institutions, as they are only one part of a cross-sector mission to address complex societal problems The case study material highlights nuances of knowledge production and learning practices in partnerships, with dual embeddedness a main feature of the findings. This provides some clues to how professionalisation as expert-making takes shape in organisations: • Depending on the type of organisations’ purpose, over its course of development there is an increase in participation in multiple networks, as opposed to reliance on a single strategic partner for knowledge artefacts and practices; • Some types of organisations are better connected within international and national networks than others and there seem to be preferences for each depending on the area of work; • The level of interpretation or adaptation of the knowledge artefacts is related to an organisation’s embeddedness locally, in turn giving it more influence within the network of key institutions; An overreaching theme across taxonomy categories (Table 1)is “professionalisation” or developing organisational “expertise”, embodied at the individual, organisational, and sector levels. Questions relevant to the exercise of power arise: Is competence in managing a dual embeddedness signals the development of a dual identity in professionalisation? Is professionalisation in this sense a sign of organisations maturing into more capable partners to the arguably more experienced (Western) institutions, shifting the power balance? Or is becoming more professional a sign of domestication to the agenda of certain powerful stakeholders, who define the boundaries of the profession? Which dominant dynamics can be observed in a broadly-defined transition country civil society, where individual participation in the form of activism may be overtaking the traditional forms of organised development work, especially with the spread of social media?

Relevância:

30.00% 30.00%

Publicador:

Resumo:

In settings of intergroup conflict, identifying contextually-relevant risk factors for youth development in an important task. In Vukovar, Croatia, a city devastated during the war in former Yugoslavia, ethno-political tensions remain. The current study utilized a mixed method approach to identify two salient community-level risk factors (ethnic tension and general antisocial behavior) and related emotional insecurity responses (ethnic and non-ethnic insecurity) among youth in Vukovar. In Study 1, focus group discussions (N=66) with mother, fathers, and adolescents 11 to 15-years-old were analyzed using the Constant Comparative Method, revealing two types of risk and insecurity responses. In Study 2, youth (N=227, 58% male, M=15.88 SD=1.12 years old) responded to quantitative scales developed from the focus groups; discriminate validity was demonstrated and path analyses established predictive validity between each type of risk and insecurity. First, community ethnic tension (i.e., threats related to war/ethnic identity) significantly predicted ethnic insecurity for all youth (β=.41, p<.001). Second, experience with community antisocial behavior (i.e., general crime found in any context) predicted non-ethnic community insecurity for girls (β=.32, p<.05), but not for boys. These findings are the first to show multiple forms of emotional insecurity at the community level; implications for future research are discussed.

Relevância:

30.00% 30.00%

Publicador:

Resumo:

As the development of a viable quantum computer nears, existing widely used public-key cryptosystems, such as RSA, will no longer be secure. Thus, significant effort is being invested into post-quantum cryptography (PQC). Lattice-based cryptography (LBC) is one such promising area of PQC, which offers versatile, efficient, and high performance security services. However, the vulnerabilities of these implementations against side-channel attacks (SCA) remain significantly understudied. Most, if not all, lattice-based cryptosystems require noise samples generated from a discrete Gaussian distribution, and a successful timing analysis attack can render the whole cryptosystem broken, making the discrete Gaussian sampler the most vulnerable module to SCA. This research proposes countermeasures against timing information leakage with FPGA-based designs of the CDT-based discrete Gaussian samplers with constant response time, targeting encryption and signature scheme parameters. The proposed designs are compared against the state-of-the-art and are shown to significantly outperform existing implementations. For encryption, the proposed sampler is 9x faster in comparison to the only other existing time-independent CDT sampler design. For signatures, the first time-independent CDT sampler in hardware is proposed. 

Relevância:

30.00% 30.00%

Publicador:

Resumo:

Metal–organic frameworks, or MOFs, have emerged as a new class of porous materials made by linking metal and organic units. The easy preparation, structural and functional tunability, ultrahigh porosity, and enormous surface areas of MOFs have led to them becoming one of the fastest growing fields in chemistry. MOFs have potential applications in numerous areas such as clean energy, adsorption and separation processes, biomedicine, and sensing. One of the most promising areas of research with MOFs is heterogeneous catalysis. This thesis describes the design and synthesis of new, carboxylate-based MOFs for use as catalysts. These materials have been characterized using diffraction, spectroscopy, adsorption, and imaging techniques. The thesis has focused on preparing highly-stable MOFs for catalysis, using post-synthetic methods to modify the properties of these crystals, and applying a combination of characterization techniques to probe these complex materials. In the first part of this thesis, several new vanadium MOFs have been presented. The synthesis of MIL-88B(V), MIL-101(V), and MIL-47 were studied using ex situ techniques to gain insight into the synthesis–structure relationships. The properties of these materials have also been studied. In the second part, the use of MOFs as supports for metallic nanoparticles has been investigated. These materials, Pd@MIL-101–NH2(Cr) and Pd@MIL-88B–NH2(Cr), were used as catalysts for Suzuki–Miyaura and oxidation reactions, respectively. The effect of the base on the catalytic activity, crystallinity, porosity, and palladium distribution of Pd@MIL-101–NH2(Cr) was studied. In the final part, the introduction of transition-metal complexes into MOFs through different synthesis routes has been described. A ruthenium complex was grafted onto an aluminium MOF, MOF-253, and an iridium metallolinker was introduced into a zirconium MOF, UiO-68–2CH3. These materials were used as catalysts for alcohol oxidation and allylic alcohol isomerization, respectively.

Relevância:

30.00% 30.00%

Publicador:

Resumo:

Das Verfahren der Lebensmitteltrocknung wird häufig angewendet, um ein Produkt für längere Zeit haltbar zu machen. Obst und Gemüse sind aufgrund ihres hohen Wassergehalts leicht verderblich durch biochemische Vorgänge innerhalb des Produktes, nicht sachgemäße Lagerung und unzureichende Transportmöglichkeiten. Um solche Verluste zu vermeiden wird die direkte Trocknung eingesetzt, welche die älteste Methode zum langfristigen haltbarmachen ist. Diese Methode ist jedoch veraltet und kann den heutigen Herausforderungen nicht gerecht werden. In der vorliegenden Arbeit wurde ein neuer Chargentrockner, mit diagonalem Luftstömungskanal entlang der Länge des Trocknungsraumes und ohne Leitbleche entwickelt. Neben dem unbestreitbaren Nutzen der Verwendung von Leitblechen, erhöhen diese jedoch die Konstruktionskosten und führen auch zu einer Erhöhung des Druckverlustes. Dadurch wird im Trocknungsprozess mehr Energie verbraucht. Um eine räumlich gleichmäßige Trocknung ohne Leitbleche zu erreichen, wurden die Lebensmittelbehälter diagonal entlang der Länge des Trockners platziert. Das vorrangige Ziel des diagonalen Kanals war, die einströmende, warme Luft gleichmäßig auf das gesamte Produkt auszurichten. Die Simulation des Luftstroms wurde mit ANSYS-Fluent in der ANSYS Workbench Plattform durchgeführt. Zwei verschiedene Geometrien der Trocknungskammer, diagonal und nicht diagonal, wurden modelliert und die Ergebnisse für eine gleichmäßige Luftverteilung aus dem diagonalen Luftströmungsdesign erhalten. Es wurde eine Reihe von Experimenten durchgeführt, um das Design zu bewerten. Kartoffelscheiben dienten als Trocknungsgut. Die statistischen Ergebnisse zeigen einen guten Korrelationskoeffizienten für die Luftstromverteilung (87,09%) zwischen dem durchschnittlich vorhergesagten und der durchschnittlichen gemessenen Strömungsgeschwindigkeit. Um den Effekt der gleichmäßigen Luftverteilung auf die Veränderung der Qualität zu bewerten, wurde die Farbe des Produktes, entlang der gesamten Länge der Trocknungskammer kontaktfrei im on-line-Verfahren bestimmt. Zu diesem Zweck wurde eine Imaging-Box, bestehend aus Kamera und Beleuchtung entwickelt. Räumliche Unterschiede dieses Qualitätsparameters wurden als Kriterium gewählt, um die gleichmäßige Trocknungsqualität in der Trocknungskammer zu bewerten. Entscheidend beim Lebensmittel-Chargentrockner ist sein Energieverbrauch. Dafür wurden thermodynamische Analysen des Trockners durchgeführt. Die Energieeffizienz des Systems wurde unter den gewählten Trocknungsbedingungen mit 50,16% kalkuliert. Die durchschnittlich genutzten Energie in Form von Elektrizität zur Herstellung von 1kg getrockneter Kartoffeln wurde mit weniger als 16,24 MJ/kg und weniger als 4,78 MJ/kg Wasser zum verdampfen bei einer sehr hohen Temperatur von jeweils 65°C und Scheibendicken von 5mm kalkuliert. Die Energie- und Exergieanalysen für diagonale Chargentrockner wurden zudem mit denen anderer Chargentrockner verglichen. Die Auswahl von Trocknungstemperatur, Massenflussrate der Trocknungsluft, Trocknerkapazität und Heiztyp sind die wichtigen Parameter zur Bewertung der genutzten Energie von Chargentrocknern. Die Entwicklung des diagonalen Chargentrockners ist eine nützliche und effektive Möglichkeit um dei Trocknungshomogenität zu erhöhen. Das Design erlaubt es, das gesamte Produkt in der Trocknungskammer gleichmäßigen Luftverhältnissen auszusetzen, statt die Luft von einer Horde zur nächsten zu leiten.

Relevância:

30.00% 30.00%

Publicador:

Resumo:

The forces surrounding the emerging economies of underdeveloped world, especially Africa has practically stifled its economic progress, growth, development and sustainability. This economic condition brings to the fore the massive onslaught of rural/urban poverty which the African continent grapples with since the post-world war II era to date. The economic misfortunes and incidence of mass poverty in Africa, vis-à-vis Nigeria is used as a point of departure in this study. The paper underscores the ideological and philosophical undertone of international capital manifesting in form of colonialism and imperialism as a major character in the historical process of underdevelopment and mass poverty in peripheral states of Africa, Asia and Latin America, respectively. Of particular interest in this study is the activities of domestic bourgeoisie elite class who have vigorously displayed some degree of lack of much needed vision and abject lack of desires to draw up workable plans to redeem the battered image of African/ Nigerian economic misfortunes. This state of affairs has practically engendered economic underdevelopment, misery and disturbing levels of poverty in the nation-state system. The paper concludes with the forward towards realizing the vision 20-20-20 objectives in the 21t century and beyond.

Relevância:

30.00% 30.00%

Publicador:

Resumo:

This study discusses the importance of establishing trust in post-acquisition integration context and how the use of e-channels facilitates or inhibits this process. The objective of this study is to analyze how the use of electronic communication channels influences the post-acquisition integration process in terms of trust establishment and overall integration efficiency, developing a framework as a result. Three sub-objectives are introduced: to find out the building blocks of trust in M&A’s, to analyse how the use of e-channels influence the process of trust establishment in post-acquisition integration context, and to define the consequences trust and use of e-channels have for the process. The theoretical background of the study includes literature and theories relating to trust establishment in post-acquisition integration context and how the use of e-channels influences the process of trust development on a general level. The empirical research is conducted as a single case study, based on key informant interviews. The interview data was collected between October 2015 and January 2016. Altogether nine interviews were realised; six with representatives from the acquiring firm and three with target firm members. Thematic analysis was selected as the main method for analysing and processing the qualitative data. This study finds that trust has an essential role in post-acquisition integration context, facilitating the integration process in various different ways. Hence, identifying the different building blocks of trust is important in order for members of the organisations to be better able establish and maintain trust. In today’s international business, the role of electronic communication channels has also increased in importance significantly and it was confirmed that these pose both challenges and possibilities for the development of interpersonal trust. One of the most important underlying factors influencing the trust levels via e-communication channels is the level of user’s comfort in using the different e-channels. Without sufficient and meaningful training, the communication conducted via these channels in inhibited in a number of ways. Hence, understanding the defining characteristics of e-communication together with the risks and opportunities related to the use of these can have far-reaching consequences for the post-acquisition integration process as a whole. The framework based on the findings and existing theory introduces the most central factors influencing the trust establishment together with the positive and negative consequences these have for the integration process. Moreover, organizational level consistency and the existence of shared guidelines on appropriate selection of communication channels according to the nature of the task at hand are seen as important

Relevância:

30.00% 30.00%

Publicador:

Resumo:

Our society is currently facing complex challenges, such us climate change, loss of biodiversity, ageing population, unemployment, to name but a few. This has created growing expectations on designers and engineers to explore, experiment and implement innovative solutions to such issues. At this critical time, if we want design to be part of the solution, we need to wonder whether we are asking designers suitable and sustainable questions. Both in post-graduate design education and in business, the brief still overwhelmingly requires designers to follow a linear problem-solving approach that focuses on product rather than strategies, services and systems. Traditional design briefs result no longer appropriate to face the challenges of our unsustainable world, as they relate to market, growth economy and human needs rather than society, business models and the needs of nature. Instead, we need to be asking questions about, for example, how we create sustainable business opportunities, how we overcome the barriers for change, or how we facilitate the process of innovation through design methodology. If the role of design is to create new visions and outline strategic directions towards a sustainable future world - for policy makers, businesses, communities and individual citizens – we need those stakeholders to create briefs for designers that allow them to do that. This paper will explain how the reframing of questions has been embedded into SustainRCA’s teaching practice in post-graduate design, art and engineering, leading to the development of new tools and methods, as well as some innovative outcomes

Relevância:

30.00% 30.00%

Publicador:

Resumo:

Morphogens are signalling molecules that play a significant role in modulation of cell fate and development. Hedgehog proteins (Hh) are morphogens that have been shown to be involved in the development of immune cells. In this study, it is demonstrated that treatment of B cells with rShh, can increase B cell activation and also promote survival of B cells at 18hours post-stimulus. Also, at this time point, there was found to be an increase in secretion of antibody isotypes and IL-6. By 40hours post-stimulus, it was observed that the level of B cell activation was apparently arrested in treated B cells, whereas the level of activation continued to rise in untreated B cells. Interestingly, it was observed that there was an increase in the percentage of; CD23-CD25+ B cells when B cells were treated with rShh and this was accompanied by an increase in apoptosis. Consistent with this finding in relation to apoptosis, there was an increased expression of the pro-apoptotic protein Bnip3 in B cells treated with rShh by 40hours post-stimulus. It was observed that there were three subsets of B cells arising in our culture at 40hours, which were all found to possess different characteristics. It was demonstrated that treatment with rShh can increase B cell differentiation towards FO-I at 18hours post-stimulus. By 40hours post-stimulus, Hh signalling can divert differentiation away from the FO-I B cell towards the T2-MZP, which was accompanied by an increase in IL-10 secretion. Gene expression analysis revealed that Hh signalling could modulate a number of molecules involved in delivering the BCR signal into the cells such as Btk, Nfatc1 and Traf2. Additionally, deletion of Dhh, showed that there was a skewed peripheral B cell development in the Dhh-/- mice. Overall, our data demonstrate that Hh signalling can regulate the development of B cells in response to an activation stimulus by strengthening the BCR signalling pathway.

Relevância:

30.00% 30.00%

Publicador:

Resumo:

The current study was carried out to evaluate the impact of a well-being curriculum based on existing knowledge of themes within PP, which contribute to well-being. The Positive Well-Being Curriculum consists of twelve ninety minute sessions delivered weekly during a school term. The twelve well-being sessions fit into four domains: positive experience, positive emotions, positive relationships, achievement and meaning (Seligman, 2007). The objectives of the study were to test the practical implications of running a well-being curriculum, to develop a range of activities within each domain and to evaluate the impact on student well-being with regard to life satisfaction, positive affectivity and subjective happiness. A pilot was carried out as preparation for the main mixed method intervention study, which was conducted in two London primary schools. Pre and post data was collected using standardised measures, focus groups and one to one interviews. Findings from the pilot demonstrated a significant increase in well-being as demonstrated by increases in: life satisfaction, positive affect and subjective happiness. Additional information was gathered which informed the content and implementation of the curriculum in the main study. The experience of taking part in the study as evidenced through qualitative and quantitative results, indicate that the Positive Well-being Curriculum was perceived by participating teachers and children to contribute positively to the well-being of the children. These findings would be of interest to educational psychologists as there is an increasing interest by schools to include creative and validated resources to support and enhance the well-being of all children. A number of useful insights were developed about the usefulness of the curriculum for children in a variety of educational settings.

Relevância:

30.00% 30.00%

Publicador:

Resumo:

Ce mémoire de maitrise porte sur deux axes principaux : la mise en diagnostic et les enjeux que cela représente pour l’individu ainsi que la question du syndrome de stress post-traumatique (SSPT) dans une population particulière, celle des militaires français. À travers une étude de différents concepts anthropologiques tels que la sous-culture militaire, l’anthropologie du corps, de la mémoire et du discours, le travail de terrain a permis de mettre de l’avant l’expérience et l’impact du diagnostic du syndrome de stress post-traumatique. Les différentes étapes de la mise en diagnostic sont présentées afin de découvrir comment est vécue l’officialisation de ce trouble. Il est alors expliqué le paradoxe propre à ce diagnostic qui est posé, peu importe le type de choc traumatique à l’origine du SSPT. Cela permet de comprendre pourquoi le diagnostic du syndrome de stress post-traumatique reste un véritable enjeu lorsqu’il est question de la population militaire. Bien que de plus en plus de recherches existent sur le sujet au Canada ou aux États-Unis, la question en France reste encore en développement. C’est pourquoi cette recherche permet de découvrir la perception du trouble pour l’individu atteint et ses proches, la prévention et la prise en charge du stress post-traumatique à travers le diagnostic proposé actuellement.