974 resultados para Routes d’invasion
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Global climate change will affect all domains of person-environment relations. Tackling climate change will require social change that can be motivated by people’s imaginings of the future of their society where such social change has occurred. We use the “collective futures” framework to examine whether beliefs about the future of society are related to present-day intentions to take climate change action. Participants from two Brazilian samples imagined their society in 2050 where climate change was mitigated and then rated how this future society would differ from Brazilian society today in terms of societal-level dysfunction and development and personal-level traits and values. To the extent that participants believed preventing climate change would result in societal development and more competence traits, they were more willing to engage in environmental citizenship activities. Individual differences in future time perspective also impacted environmental citizenship intention. Societal development and consideration of future consequences seem to be distinct routes by which future thinking influence climate change action.
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Scarring is a significant medical burden; financially to the health care system and physically and psychologically for patients. Importantly, there have been numerous case reports describing the occurrence of cancer in burn scars. Currently available therapies are not satisfactory due to their undesirable side-effects, complex delivery routes, requirements for long-term use and/or expense. Radix Arnebiae (Zi Cao), a perennial herb, has been clinically applied to treat burns and manage scars for thousands of years in Asia. Shikonin, an active component extracted from Radix Arnebiae, has been demonstrated to induce apoptosis in cancer cells. Apoptosis is an essential process during scar tissue remodelling. It was therefore hypothesized that Shikonin may induce apoptosis in scar-associated cells. This investigation presents the first detailed in vitro study examining the functional responses of scar-associated cells to Shikonin, and investigates the mechanisms underlying these responses. The data obtained suggests that Shikonin inhibits cell viability and proliferation and reduces detectable collagen in scar-derived fibroblasts. Further investigation revealed that Shikonin induces apoptosis in scar fibroblasts by differentially regulating the expression of caspase 3, Bcl-2, phospho-Erk1/2 and phospho-p38. In addition, Shikonin down-regulates the expression of collagen I, collagen III and alpha-smooth muscle actin genes hence attenuating collagen synthesis in scar-derived fibroblasts. In summary, it is demonstrated that Shikonin induces apoptosis and decreases collagen production in scar-associated fibroblasts and may therefore hold potential as a novel scar remediation therapy.
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This paper reviews the state-of-the-art in the automation of underground mining vehicles and reports on the development of an autonomous navigation system under development through the CMTE with sponsorship arranged by AMIRA. Past attempts at automating LHDs and haul trucks are described and their particular strengths and weaknesses are discussed. The auto-guidance system being developed overcomes some of the limitations of state-of-the-art prototype æcommercialÆ systems. It can be retrofitted to existing remote controlled vehicles, uses minimum installed infrastructure and is flexible enough for rapid relocation to alternate routes. The navigation techniques use data fusion of two separate sets of sensors combining natural feature recognition, nodal maps and inertial navigation techniques. Collision detection is incorporated and people and other traffic are excluded from the tramming area. This paper describes the work being done by the group with regard to auto-tramming and also outlines the future goals.
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Background Globally, over 800 000 children under five die each year from infectious diseases caused by Streptococcus pneumoniae. To understand genetic relatedness between isolates, study transmission routes, assess the impact of human interventions e.g. vaccines, and determine infection sources, genotyping methods are required. The ‘gold standard’ genotyping method, Multi-Locus Sequence Typing (MLST), is useful for long-term and global studies. Another genotyping method, Multi-Locus Variable Number of Tandem Repeat Analysis (MLVA), has emerged as a more discriminatory, inexpensive and faster technique; however there is no universally accepted method and it is currently suitable for short-term and localised epidemiology studies. Currently Australia has no national MLST database, nor has it adopted any MLVA method for short-term or localised studies. This study aims to improve S. pneumoniae genotyping methods by modifying the existing MLVA techniques to be more discriminatory, faster, cheaper and technically less demanding than previously published MLVA methods and MLST. Methods Four different MLVA protocols, including a modified method, were applied to 317 isolates of serotyped invasive S. pneumoniae isolated from sterile body sites of Queensland children under 15 years from 2007–2012. MLST was applied to 202 isolates for comparison. Results The modified MLVA4 is significantly more discriminatory than the ‘gold standard’ MLST method. MLVA4 has similar discrimination compared to other MLVA techniques in this study). The failure to amplify particular loci in previous MLVA methods were minimised in MLVA4. Failure to amplify BOX-13 and Spneu19 were found to be serotype specific. Conclusion We have modified a highly discriminatory MLVA technique for genotyping Queensland invasive S. pneumoniae. MLVA4 has the ability to enhance our understanding of the pneumococcal epidemiology and the changing genetics of the pneumococcus in localised and short-term studies.
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Recent 'Global Burden of Disease' studies have provided quantitative evidence of the significant role air pollution plays as a human health risk factor (Lim et al., The Lancet, 380: 2224–2260, 2012). Tobacco smoke, including second hand smoke, household air pollution from solid fuels and ambient particulate matter are among the top risks, leading to lower life expectancy around the world. Indoor air constitutes an environment particularly rich in different types of pollutants, originating from indoor sources, as well as penetrating from outdoors, mixing, interacting or growing (when considering microbes) under the protective enclosure of the building envelope. Therefore, it is not a simple task to follow the dynamics of the processes occurring there, or to quantify the outcomes of the processes in terms of pollutant concentrations and other characteristics. This is further complicated by limitations such as building access for the purpose of air quality monitoring, or the instrumentation which can be used indoors, because of their possible interference with the occupants comfort (due to their large size, noise generated or amount of air drawn). European studies apportioned contributions of indoor versus outdoor sources of indoor air contaminants in 26 European countries and quantified IAQ associated DALYs (Disability-Adjusted Life Years) in those countries (Jantunen et al., Promoting actions for healthy indoor air (IAIAQ), European Commission Directorate General for Health and Consumers, Luxembourg, 2011). At the same time, there has been an increase in research efforts around the world to better understand the sources, composition, dynamics and impacts of indoor air pollution. Particular focus has been directed towards the contemporary sources, novel pollutants and new detection methods. The importance of exposure assessment and personal exposure, the majority of which occurs in various indoor micro¬environments, has also been realized. Overall, this emerging knowledge has been providing input for global assessments of indoor environments, the impact of indoor pollutants and their science based management and control. It was a major outcome of recent international conferences that interdisciplinarity and especially a better colla¬boration between exposure and indoor sciences would be of high benefit for the health related evaluation of environmental stress factors and pollutants. A very good example is the combination of biomonitoring and indoor air, particle and dust analysis to study the exposure routes of semi volatile organic compounds (SVOCs). We have adopted the idea of combining the forces of exposure and indoor sciences for this Special Issue, identified new and challenging topics and have attracted colleagues who are top researchers in their field to provide their inputs. The Special Issue includes papers, which collectively present advances in current research topics and in our view, build the bridge between indoor and exposure sciences.
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The benefits of virtual communities in increasing firms' profits, instilling knowledge in consumers, and enhancing consumers' social experience and enjoyment are widely recognised. However, relatively little is known about how the use of a virtual community could influence consumers' emotional well-being. This study examines the relationships among virtual community features (structural and experiential routes) as antecedents of virtual community engagement, including quality of use of virtual communities (time spent online and level of information exchange), electronic word-of-mouth (eWOM) purchasing behaviour, and consumers' emotional experience. Furthermore, by extending the cultural perspective to virtual community engagement, this study examines the role of collectivistic values on the aforementioned relationships. The proposed hypotheses are tested on the basis of data collected from 286 members of different virtual communities in Taiwan. The results partially support the theory that features of virtual communities influenced the quality of use, which then has a subsequent effect on consumer eWOM purchasing and emotional well-being. The results of the empirical analysis add credence to the proposed relationships. The role of collectivistic values is also partially supported. A detailed discussion of the findings and limitations of this study is provided.
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This thesis examined the level of food safety compliance with government regulations and investigated routes of microbiological contaminations in raw finfish within Vietnamese domestic seafood distribution chains. Findings from direct observation, microbiological analysis and employee surveys were synthesized to identify the main factors affecting food safety and hygiene practices of fish distributors. The studies produced clear recommendations for food safety management in the domestic distribution chains. The findings may contribute to national efforts to decrease the risks of fish-borne illness for consumers in Vietnam.
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Employees’ safety climate perceptions dictate their safety behavior because individuals act based on their perceptions of reality. Extensive empirical research in applied psychology has confirmed this relationship. However, rare efforts have been made to investigate the factors contributing to a favorable safety climate in construction research. As an initial effort to address the knowledge gap, this paper examines factors contributing to a psychological safety climate, an operationalization of a safety climate at the individual level, and, hence, the basic element of a safety climate at higher levels. A multiperspective framework of contributors to a psychological safety climate is estimated by a structural equation modeling technique using individual questionnaire responses from a random sample of construction project personnel. The results inform management of three routes to psychological safety climate: a client’s proactive involvement in safety management, a workforce-friendly workplace created by the project team, and transformational supervisors’ communication about safety matters with the workforce. This paper contributes to the field of construction engineering and management by highlighting a broader contextual influence in a systematic formation of psychological safety climate perceptions.
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Our understanding of the origin and fate of the IgE-switched B cell has been markedly improved by studies in mouse models. The immediate precursor of the IgE-switched B cell is either a relatively naive nonswitched B cell or a mature IgG-switched B cell. These 2 routes are referred to as the direct and indirect pathways, respectively. IgE responses derived from each pathway differ significantly, largely reflecting the difference in time spent in a germinal center and thus time for clonal expansion, somatic hypermutation, affinity maturation, and acquisition of a memory phenotype. The clinical and therapeutic implications for IgE responses in human subjects are still a matter of debate, largely because the immunization procedures used in the animal models are significantly different from classical atopic sensitization to allergens from pollen and mites. On the basis of the limited information available, it seems likely that these atopic IgE responses are characterized by a relatively low IgG/IgE ratio, low B-cell memory, and modest affinity maturation, which fits well with the direct switching pathway. It is still unresolved how the IgE response evolves to cover a wide epitope repertoire involving many epitopes per allergen, as well as many different allergens from a single allergen source. © 2013 American Academy of Allergy, Asthma & Immunology.
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This study investigated a new performance indicator to assess climbing fluency (smoothness of the hip trajectory and orientation of a climber using normalized jerk coefficients) to explore effects of practice and hold design on performance. Eight experienced climbers completed four repetitions of two, 10-m high routes with similar difficulty levels, but varying in hold graspability (holds with one edge vs holds with two edges). An inertial measurement unit was attached to the hips of each climber to collect 3D acceleration and 3D orientation data to compute jerk coefficients. Results showed high correlations (r = .99, P < .05) between the normalized jerk coefficient of hip trajectory and orientation. Results showed higher normalized jerk coefficients for the route with two graspable edges, perhaps due to more complex route finding and action regulation behaviors. This effect decreased with practice. Jerk coefficient of hip trajectory and orientation could be a useful indicator of climbing fluency for coaches as its computation takes into account both spatial and temporal parameters (ie, changes in both climbing trajectory and time to travel this trajectory)
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In this paper, we introduce a path algebra well suited for navigation in environments that can be abstracted as topological graphs. From this path algebra, we derive algorithms to reduce routes in such environments. The routes are reduced in the sense that they are shorter (contain fewer edges), but still connect the endpoints of the initial routes. Contrary to planning methods descended from Disjktra’s Shortest Path Algorithm like D , the navigation methods derived from our path algebra do not require any graph representation. We prove that the reduced routes are optimal when the graphs are without cycles. In the case of graphs with cycles, we prove that whatever the length of the initial route, the length of the reduced route is bounded by a constant that only depends on the structure of the environment.
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Synthetic routes leading to 12 L-phenylalanine based mono- and bipolar derivatives (1-12) and an in-depth study of their structure-property relationship with respect to gelation have been presented. These include monopolar systems such as N-[(benzyloxy)carbonyl]-L-phenylalanine-N-alkylamides and the corresponding bipolar derivatives with flexible and rigid spacers such as with 1,12-diaminododecane and 4,4'-diaminodiphenylmethane, respectively. The two ends of the latter have been functionalized with N-[(benzyloxy)carbonyl]-L-phenylalanine units via amide connection. Another bipolar molecule was synthesized in which the middle portion of the hydrocarbon segment contained polymerizable diacetylene unit. To ascertain the role of the presence of urethane linkages in the gelator molecule protected L-phenylalanine derivatives were also synthesized in which the (benzyloxy)carbonyl group has been replaced with (tert-butyloxy)carbonyl, acetyl, and benzoyl groups, respectively. Upon completion of the synthesis and adequate characterization of the newly described molecules, we examined the aggregation and gelation properties of each of them in a number of solvents and their mixtures. Optical microscopy and electron microscopy further characterized the systems that formed gels. Few representative systems, which showed excellent gelation behavior was, further examined by FT-IR, calorimetric, and powder X-ray diffraction studies. To explain the possible reasons for gelation, the results of molecular modeling and energy-minimization studies were also included. Taken together these results demonstrate the importance of the presence of (benzyloxy)carbonyl unit, urethane and secondary amide linkages, chiral purities of the headgroup and the length of the alkyl chain of the hydrophobic segment as critical determinants toward effective gelation.
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Työ käsittelee Rooman laivaston kehitystä, toimintaa ja osallistumista laajenemispolitiikkaan, jossa Rooma kasvoi kaupunkivaltiosta Välimeren hallitsijaksi. Rooma on aikaisemmissa tutkimuksissa nähty maavaltiona vailla kiinnostusta merenkulkuun. On katsottu, että ainoa merkittävä merisota Rooman historiassa on ensimmäinen puunilaissota (264-241 eKr.) ja että siinäkin roomalaiset (jotka historioitsija Polybius kuvaa vasta-alkajiksi) menestyivät Karthagoa vastaan turvautumalla laskusiltoihin, joiden avulla he saattoivat muuttaa meritaistelun maataisteluksi. Polybiuksen kuvaukseen on aina tähän asti luotettu. On katsottu että Roomalla ei ollut laivastoa ennen ensimmäistä puunilaissotaa ja että Rooma kaikissa sodissaan panosti merisodankäyntiin mahdollisimman vähän. Tämä työ pyrkii kumoamaan nämä käsitykset. Laivasto oli osallisena ja ehdottoman välttämätön kaikissa Rooman laajenemispolitiikan käänteissä. Arkeologian tiedot osoittavat, että ennen ensimmäistä puunilaissotaa Rooma kehittyi ja siitä tuli merkittävä kaupunki nimenomaan kaupankäynnin ja ulkomaisten kontaktien seurauksena. Se ei siis ollut puhdas agraarivaltio. Roomalaisilla oli laivasto jo viimeistään 500-luvulta lähtien eKr. ja sitä käytettiin Rooman laajentaessa valtaansa Italiassa. Näin ollen ensimmäisessä puunilaissodassa läntisen Välimeren herruudesta kilpaili kaksi merivaltiota, Rooma ja Karthago. Toinen puunilaissota (218-201) tunnetaan yleensä Hannibalin tulosta Alppien yli Italiaan, mutta se oli myöskin merkittävä merisota ja karthagolaiset hävisivät sen nimenomaan merellä. Rooma osallistui kilpailuun itäisen Välimeren hallinnasta ja kukisti Makedonian ja Syyrian laivastot, jotka eivät olleet mitenkään Rooman laivaston veroisia. Kaikista Rooman vastustajista Karthagolla olisi ollut suurin mahdollisuus pysäyttää Rooman laivaston voittokulu toisessa puunilaissodassa. Laivastoa käytettiin moniin eri tarkoituksiin. Suuret meritaistelut eivät ole ainoa osoitus laivastojen mukanaolosta ja merkityksestä, vaan on myös otettava huomion sotalaivojen rakenne ja toimintaedellytykset. Sotalaivat oli rakennettu taisteluita varten ja niissä oli hyvin niukasti säilytystilaa. Niiden oli päästävä laskemaan maihin aina kun miehistö tarvitsi vettä, ruokaa ja lepoa. Laivastot saattoivat toimia vain niiden rannikoiden tuntumassa, joiden satamiin ja laskupaikkoihin niillä oli turvallinen pääsy. Roomalaiset olivat hyvin tietoisia tästä. Suuret merentakaiset sotaretket Afrikkaan, Espanjaan, Kreikkaan ja Vähän-Aasian rannikolle perustuivat kaikki siihen, että Rooman laivasto hallitsi purjehdusreittejä ja sopivia laskupaikkoja ja saattoi huolehtia joukkojen ja varusteiden kuljettamisesta kaukana taisteleville armeijoille. Samalla Rooman laivasto kävi itsenäistä sotaa merellä ja haastoi ja kukisti kaikki Välimeren merivaltiot. 130-luvulle eKr. tultaessa se oli lyönyt vihollisensa ja riisunut aseista liittolaisensa; Rooman laivasto hallitsi Välimerta yksin.
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Earlier studies have shown that the speed of information transmission developed radically during the 19th century. The fast development was mainly due to the change from sailing ships and horse-driven coaches to steamers and railways, as well as the telegraph. Speed of information transmission has normally been measured by calculating the duration between writing and receiving a letter, or between an important event and the time when the news was published elsewhere. As overseas mail was generally carried by ships, the history of communications and maritime history are closely related. This study also brings a postal historical aspect to the academic discussion. Additionally, there is another new aspect included. In business enterprises, information flows generally consisted of multiple transactions. Although fast one-way information was often crucial, e.g. news of a changing market situation, at least equally important was that there was a possibility to react rapidly. To examine the development of business information transmission, the duration of mail transport has been measured by a systematic and commensurable method, using consecutive information circles per year as the principal tool for measurement. The study covers a period of six decades, several of the world's most important trade routes and different mail-carrying systems operated by merchant ships, sailing packets and several nations' steamship services. The main sources have been the sailing data of mail-carrying ships and correspondence of several merchant houses in England. As the world's main trade routes had their specific historical backgrounds with different businesses, interests and needs, the systems for information transmission did not develop similarly or simultaneously. It was a process lasting several decades, initiated by the idea of organizing sailings in a regular line system. The evolution proceeded generally as follows: originally there was a more or less irregular system, then a regular system and finally a more frequent regular system of mail services. The trend was from sail to steam, but both these means of communication improved following the same scheme. Faster sailings alone did not radically improve the number of consecutive information circles per year, if the communication was not frequent enough. Neither did improved frequency advance the information circulation if the trip was very long or if the sailings were overlapping instead of complementing each other. The speed of information transmission could be improved by speeding up the voyage itself (technological improvements, minimizing the waiting time at ports of call, etc.) but especially by organizing sailings so that the recipients had the possibility to reply to arriving mails without unnecessary delay. It took two to three decades before the mail-carrying shipping companies were able to organize their sailings in an optimal way. Strategic shortcuts over isthmuses (e.g. Panama, Suez) together with the cooperation between steamships and railways enabled the most effective improvements in global communications before the introduction of the telegraph.
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Approximately 125 prehistoric rock paintings have been found in the modern territory of Finland. The paintings were done with red ochre and are almost without exception located on steep lakeshore cliffs associated with ancient water routes. Most of the sites are found in the central and eastern parts of the country, especially on the shores of Lakes Päijänne and Saimaa. Using shore displacement chronology, the art has been dated to ca. 5000 – 1500 BC. It was thus created mainly during the Stone Age and can be associated with the so-called ‘Comb Ware’ cultures of the Subneolithic period. The range of motifs is rather limited, consisting mainly of schematic depictions of stick-figure humans, elks, boats, handprints and geometric signs. Few paintings include any evidence of narrative scenes, making their interpretation a rather difficult task. In Finnish archaeological literature, the paintings have traditionally been associated with ’sympathetic’ hunting magic, or the belief that the ritual shooting of the painted animals would increase hunting luck. Some writers have also suggested totemistic and shamanistic readings of the art. This dissertation is a critical review of the interpretations offered of Finnish rock art and an exploration of the potentials of archaeological and ethnographic research in increasing our knowledge of its meaning. Methods used include ’formal’ approaches such as archaeological excavation, landscape analysis and the application of neuropsychological research to the study of rock art, as well as ethnographically ’informed’ approaches that make use of Saami and Baltic Finnish ethnohistorical sources in interpretation. In conclusion, it is argued that although North European hunter-gatherer rock art is often thought to lie beyond the reach of ‘informed’ knowledge, the exceptional continuity of prehistoric settlement in Finland validates the informed approach in the interpretation of Finnish rock paintings. The art can be confidently associated with shamanism of the kind still practiced by the Saami of Northern Fennoscandia in the historical period. Evidence of similar shamanistic practices, concepts and cosmology are also found in traditional Finnish-Karelian epic poetry. Previous readings of the art based on ‘hunting magic’ and totemism are rejected. Most of the paintings appear to depict experiences of falling into a trance, of shamanic metamorphosis and trance journeys, and of ‘spirit helper’ beings comparable to those employed by the Saami shaman (noaidi). As demonstrated by the results of an excavation at the rock painting of Valkeisaari, the painted cliffs themselves find a close parallel in the Saami cult of the 'sieidi', or sacred cliffs and boulders worshipped as expressing a supernatural power. Like the Saami, the prehistoric inhabitants of the Finnish Lake Region seem to have believed that certain cliffs were ’alive’ and inhabited by the spirit helpers of the shaman. The rock paintings can thus be associated with shamanic vision quests, and the making of ‘art’ with an effort to socialize the other members of the community, especially the ritual specialists, with trance visions. However, the paintings were not merely to be looked at. The red ochre handprints pressed on images of elks, as well as the fact that many paintings appear ’smeared’, indicate that they were also to be touched – perhaps in order to tap into the supernatural potency inherent in the cliff and in the paintings of spirit animals.