926 resultados para Africa, East -- Description and travel.
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Maize grown in eastern and southern Africa experiences random occurrences of drought. This uncertainty creates difficulty in developing superior varieties and their agronomy. Characterisation of drought types and their frequencies could help in better defining selection environments for improving resistance to drought. We used the well tested APSIM maize model to characterise major drought stress patterns and their frequencies across six countries of the region including Ethiopia, Kenya, Tanzania, Malawi, Mozambique and Zimbabwe. The database thus generated covered 35 sites, 17 to 86 years of daily climate records, 3 varieties and 3 planting densities from a total of 11,174 simulations. The analysis identified four major drought environment types including those characterised by low-stress which occurred in 42% of the years, mid-season drought occurring in 15% of the years, late-terminal stress which occurred in 22% of the years and early-terminal drought occurring in 21% of the years. These frequencies varied in relation to sites, genotypes and management. The simulations showed that early terminal stress could result in a yield reduction of 70% compared with low-stress environmental types. The study presents the importance of environmental characterization in contributing to maize improvement in eastern and southern Africa.
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Coptotermes Wasmann (Isoptera: Rhinotermitidae) is one of the most economically important subterranean termite genera and some species are successful invaders. However, despite its important pest status, the taxonomic validity of many named Coptotermes species remains unclear. In this study, we reviewed all named species within the genus and investigated evidence supporting the validity of each named species. Species were systematically scrutinized according to the region of their original description: Southeast Asia, India, China, Africa, the Neotropics, and Australia. We estimate that of the currently 69 named species described by accepted nomenclatural rules, only 21 taxa have solid evidence for validity, 44 names have uncertain status, and the remaining species names should be synonymized or were made unavailable. Species with high degrees of invasiveness may be known under additional junior synonyms due to independent parochial descriptions. Molecular data for a vast majority of species are scarce and significant effort is needed to complete the taxonomic and phylogenetic revision of the genus. Because of the wide distribution of Coptotermes, we advocate for an integrative taxonomic effort to establish the distribution of each putative species, provide specimens and corresponding molecular data, check original descriptions and type specimens (if available), and provide evidence for a more robust phylogenetic position of each species. This study embodies both consensus and contention of those studying Coptotermes and thus pinpoints the current uncertainty of many species. This project is intended to be a roadmap for identifying those Coptotermes species names that need to be more thoroughly investigated, as an incentive to complete a necessary revision process.
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Providing on line travel time information to commuters has become an important issue for Advanced Traveler Information Systems and Route Guidance Systems in the past years, due to the increasing traffic volume and congestion in the road networks. Travel time is one of the most useful traffic variables because it is more intuitive than other traffic variables such as flow, occupancy or density, and is useful for travelers in decision making. The aim of this paper is to present a global view of the literature on the modeling of travel time, introducing crucial concepts and giving a thorough classification of the existing tech- niques. Most of the attention will focus on travel time estimation and travel time prediction, which are generally not presented together. The main goals of these models, the study areas and methodologies used to carry out these tasks will be further explored and categorized.
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The 23rd Annual Symposium on Sea Turtle Biology and Conservation was held between 17 and 21 March 2003 at The Legend Hotel in Kuala Lumpur, Malaysia, hosted by the Community Conservation Network, Hawaii, and WWF-Malaysia. The meeting was attended by slightly more than 300 participants representing 73 countries, a dramatic drop in participation from previous years brought about in no small part by the looming war in the middle east region and concerns over travel safety. For 22 years the Symposium had bee an Americas-based event, even though it is the annual gathering of the "international" sea turtle society, and with the move to Malaysia, the Symposium hoped to raise the awareness among the general public of the plight of amrine turtles in Southeast Asia, and share the enormous exspertise of the world authorities on sea turtles with this so-far underrepresented region. Adopting the thems, "Living With Turtles", the Symposium had a very personal flavour, and the smaller number of participants made it possible to make and renew acquaintances, and have time for discussion between sessions. While the travel safety concern excuse was often quoted, it was a pity, particularly to the large contingent of people who attended the event for the first time from underrepresented regions, that many of the household names linked to marine turtle biology and conservation were not present to share their knowledge and promote the global concerns on the plight of turtle populations.
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The Indo-Pacific lionfish, Pterois miles and P. volitans, have recently invaded the U.S. east coast and the Caribbean and pose a significant threat to native reef fish communities. Few studies have documented reproduction in pteroines from the Indo-Pacific. This study provides a description of oogenesis and spawn formation in P. miles and P. volitans collected from offshore waters of North Carolina, U.S.A and the Bahamas. Using histological and laboratory observations, we found no differences in reproductive biology between P. miles and P. volitans. These lionfish spawn buoyant eggs that are encased in a hollow mass of mucus produced by specialized secretory cells of the ovarian wall complex. Oocytes develop on highly vascularized peduncles with all oocyte stages present in the ovary of spawning females and the most mature oocytes placed terminally, near the ovarian lumen. Given these ovarian characteristics, these lionfish are asynchronous, indeterminate batch spawners and are thus capable of sustained reproduction throughout the year when conditions are suitable. This mode of reproduction could have contributed to the recent and rapid establishment of these lionfish in the northwestern Atlantic and Caribbean.
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The mobile cloud computing paradigm can offer relevant and useful services to the users of smart mobile devices. Such public services already exist on the web and in cloud deployments, by implementing common web service standards. However, these services are described by mark-up languages, such as XML, that cannot be comprehended by non-specialists. Furthermore, the lack of common interfaces for related services makes discovery and consumption difficult for both users and software. The problem of service description, discovery, and consumption for the mobile cloud must be addressed to allow users to benefit from these services on mobile devices. This paper introduces our work on a mobile cloud service discovery solution, which is utilised by our mobile cloud middleware, Context Aware Mobile Cloud Services (CAMCS). The aim of our approach is to remove complex mark-up languages from the description and discovery process. By means of the Cloud Personal Assistant (CPA) assigned to each user of CAMCS, relevant mobile cloud services can be discovered and consumed easily by the end user from the mobile device. We present the discovery process, the architecture of our own service registry, and service description structure. CAMCS allows services to be used from the mobile device through a user's CPA, by means of user defined tasks. We present the task model of the CPA enabled by our solution, including automatic tasks, which can perform work for the user without an explicit request.
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Beginning with a panoramic analysis of the role played by East Timorese poets in the struggle for liberation from Portuguese and Indonesian colonial rule, this article examines the extent to which an East Timorese national identity and unity repeatedly featured in the poetry of the 1970s and 80s are represented in contemporary Timorese literary production. By reading the work of the novelist Luís Cardoso, and the poets Abé Barreto and Celso Oliveira, the article also assesses whether the independent nation envisioned earlier by those such as Borja da Costa, Fernando Sylvan and Xanana Gusmão, has been realised. In doing so, critical attention is brought to bear on the intimate relationship between the specific material and political circumstances of East Timor and the literature produced in colonial and postcolonial moments in the nation’s history.
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An increase in edge area reduces the effective size of habitat fragments and thus the area available for habitat-interior specialists. However, it is unclear how edge effects compare at different ecotones in the same system. We investigated the response of a small mammal community associated with Afromontane forests to edge effects at three different habitat transitions: natural forest to grassland (natural edge, structurally different vegetation types), natural forest to mature plantation (human-altered edge, structurally similar vegetation types) and natural forest to harvested plantation (human-altered edge, structurally different vegetation types). We predicted that edge effects should be less severe at natural ecotones and at similarly structured contiguous vegetation types than human-altered ecotones and differently structured contiguous vegetation types, respectively. We found that forest species seemed to avoid all habitat edges in our study area. Surprisingly, natural edges supported a less diverse small mammal community than human-altered forest edges. However, edge effects were observed deeper into native forests surrounded by mature alien plantations (and more so at harvested plantations) than into native forests surrounded by native grasslands. The net effect of mature plantations was therefore to reduce the functional size of the natural forest by creating a larger edge. We suggest that when plantations are established a buffer zone of natural vegetation be left between natural forests and newly established plantations to mitigate the negative effects of plantation forestry.
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This volume explores the role and history of migration and diaspora within the Portuguese empire, investigating what role colonial communities and diaspora have had in shaping the Portuguese empire and its heritage. The book consists of twelve case studies which look at topics such as Portuguese migration to Africa, the Ismaili and the Swiss presence in Mozambique, the Goanese in East Africa, the Chinese in Brazil, and the history of the African presence in Portugal.
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Background: Rift Valley fever (RVF) is a zoonotic arbovirosis for which the primary hosts are domestic livestock (cattle, sheep and goats). RVF was first described in South Africa in 1950-1951. Mechanisms for short and long distance transmission have been hypothesised, but there is little supporting evidence. Here we describe RVF occurrence and spatial distribution in South Africa in 2008-11, and investigate the presence of a contagious process in order to generate hypotheses on the different mechanisms of transmission. Methodology/Principal Findings: A total of 658 cases were extracted from World Animal Health Information Database. Descriptive statistics, epidemic curves and maps were produced. The space-time K-function was used to test for evidence of space-time interaction. Five RVF outbreak waves (one in 2008, two in 2009, one in 2010 and one in 2011) of varying duration, location and size were reported. About 70% of cases (n = 471) occurred in 2010, when the epidemic was almost country-wide. No strong evidence of space-time interaction was found for 2008 or the second wave in 2009. In the first wave of 2009, a significant space-time interaction was detected for up to one month and over 40 km. In 2010 and 2011 a significant intense, short and localised space-time interaction (up to 3 days and 15 km) was detected, followed by one of lower intensity (up to 2 weeks and 35 to 90 km). Conclusions/Significance: The description of the spatiotemporal patterns of RVF in South Africa between 2008 and 2011 supports the hypothesis that during an epidemic, disease spread may be supported by factors other than active vector dispersal. Limitations of under-reporting and space-time K-function properties are discussed. Further spatial analyses and data are required to explain factors and mechanisms driving RVF spread. © 2012 Métras et al.
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Hepatocellular carcinoma (HCC) has a high mortality in East Asia and Sub-Saharan Africa, two regions where the main etiologic factors are chronic infections with hepatitis B vir-us and dietary exposure to aflatoxin. A single base substitution at the third nucleotide of codon 249 of TP53 (R249S) is common in HCC in these regions and has been associated with aflatoxin-DNA adducts. To determine whether R249S may be detected in plasma DNA before HCC diagnosis, we conducted a case-control study nested in a cohort of adult chronic hepatitis B virus carriers from Qidong County, People's Republic of China. Of the 234 plasma specimens that yielded adequate DNA, only 2 (0.9%) were positive for R249S by restriction fragment length polymorphisms, and both of them were controls. Of the 249 subjects tested for aflatoxin-albumin adducts, 168 (67%) were positive, with equal distribution between cases and controls. Aflatoxin-albumin adduct levels were low in the study, suggesting an overall low ongoing exposure to aflatoxin in this cohort. The R249S mutation was detected in 11 of 18 (61%) available tumor tissues. To assess whether low levels of mutant DNA were detectable in pre-diagnosis plasma, 14 plasma specimens from these patients were analyzed by short oligonucleotide mass analysis. Nine of them (64%) were found to be positive. Overall, these results suggest that HCC containing R249S can occur in the absence of significant recent exposure to aflatoxins. The use of short oligonucleotide mass analysis in the context of low ongoing aflatoxin exposure may allow the detection of R249S in plasma several months ahead of clinical diagnosis. (Cancer Epidemiol Biomarkers Prev 2009;18(5):1638-43)
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Makeshift shelters are becoming increasingly evident in European cities as a consequence of the momentous influx of refugees seeking asylum in European countries. These individuals have endured long gruelling journeys to reach their target countries, often having to have survived appalling living conditions (figure 1a). One of the routes chosen by migrants is that from East Africa, through Sudan and Libya before reaching North Africa and eventually Europe (see figure 1b). Not unsurprisingly, this has led to the introduction of infectious diseases rarely encountered in developed nations, most notably louse-borne relapsing fever (LBRF).
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The contemporary science of sport and exercise psychology requires the standardisation of mental skills questionnaires to facilitate accurate assessment of and intervention for individuals and groups in various health and sport related contexts. The study presents international research findings regarding the standardisation of a Mental Skills Scale with a sample of university students (N=420) from South Africa (n=211) and the United Kingdom (n=209) respectively. Although further international and national standardisation in both English and other languages is recommended, factor and reliability analyses indicated satisfactory validity and reliability of the current English version of the scale.
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The interfaces between the intrapsychic, interactional, and intergenerational domains are a new frontier. As a pilot, we exposed ourselves to a complex but controllable situation as viewed by people whose main interest is in one of the three interfaces; we also fully integrated the subjects in the team, to learn about their subjective perspectives and to provide them with an enriching experience. We started with a brief "triadification" sequence (i.e., moving from a "two plus one" to a "three together" family organization). Considering this sequence as representing at a micro level many larger family transitions, we proceeded with a microanalytic interview, a psychodynamic investigation, and a family interview. As expected, larger patterns of correspondences are emerging. Central questions under debate are: What are the most appropriate units at each level of description and what are their articulations between these levels? What is the status of "triadification"? Les interfaces entre les domaines intrapsychiques, interactionnels et intergénérationnels représentent une nouvelle frontiére. A titre exploratoire, nous nous sommes exposés à une situation complexe mais contrǒlable ainsi que le voient ceux dont I'intérět principal se porte sur l'une de ces trois interfaces. Nous avons aussi entièrement intégré les sujets dans l'équipe, de facon à comprendre leur perspective subjective et à leur offrir une expérience enrichissante. Nous avons commencé avec une brève séquence de "triadification," c'est-à-dire passer d'une organisation familiale "deux plus un" à Ltne organisation familiale "trois (add sentenc)ensemble." Considérant cette séquence comme representative à un niveau microscopique de transitions familiales bien plus larges, nous avons procedé à l'entretien microanalytique, à une enquěte psychodynamique et à un entretien familial. Comme prévu, de grands patterns de correspondances émergent. Les questions essentielles sur lesquelles portent le débat sont: quelles les unités les plus appropiées à chaque niveau de description et quelles sont les articulations entre ces niveaux? Quel est le statut de la "triadification"?
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Conflicts over human rights in relations between East Asia and the West have increased since the end of the Cold War. Western governments express concern about human rights standards in East Asian countries. In the East, these expressions have been perceived as interference in internal affairs. Due to dramatic economic development, East Asian nations recently have gained in pride and self-confidence as global actors. Such development is observed with suspicion in the West. Concerned about the decline of global U.S. influence, some American scholars have re-invented the notion of "culture" to point at an alleged East Asian threat. Also East Asian statesmen use the cultural argument by claiming the existence of so-called 'Asian values', which they allege are the key to Eastern economic success. This thesis argues that issues of human rights in East-West relations are not only a consequence of well-intended concern by Western governments regarding the human rights and welfare of the citizens of East Asian nations, but are in fact dominated by and used as a pawn in interplay with more complicated questions of global power and economic relations between East and West. The thesis reviews the relevance of culture in East-West relations. In the West, particularly Samuel P. Huntington with his prediction of the Clash of Civilizations stands out. Singapore's Lee Kuan Yew has been very vocal on the Eastern side. Whereas the West tries to cope with its decrease of global influence, after hundreds of years under Western hegemonism, the East believes in an Asian way of development without interference form the West. Most of this dispute revolves around the issue of human rights. The West claims the universality of rights which in fact emphasizes political and civil rights. Western countries critizise poor human rights standards in East Asia. The East, in return, accuses the West of hypocritical policies that seek global dominance. East Asian governments assert that due to a different stage of development they have to stress first their rights to development in order to assure stability. In particular, China argues this way. The country's leadership, however, shows concern about human rights and has already improved its human rights record over the past years. This thesis analyses the dispute over human rights in a case study on Germany and China. Both countries have a mutual interest in trade relations which has conflicted with Germany's criticism of China's problematic human rights record. In 1996, the two countries clashed after the German parliament passed a resolution condemning China's treatment of Tibet. This caused a lot of damage to the Chinese-German relationship which in the course of the year went back to normality. In the light of these frictions a German human rights policy that focuses on unspectacular grass-roots support of China, for example in strengthening China's legal system, would be preferable. Such co-operation must be based on mutual respect.