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This chapter considers Ceylon as a crossroads by way of a close reading of a Malay Compendium from early nineteenth-century Colombo. The references and texts it contains are clear indicators of intellectual and religious connections that the Malays maintained with the archipelago and Arabia. And this realization, in turn, suggests that, rather than viewing the Malays in Ceylon as occupying a distant, marginal corner of a vast Malay sphere, their physical and figurative location between the Malay and Arab worlds signifies that crossroads, connections and movement are more appropriate conceptual categories for considering their case than is marginality. Within the Compendium and other nineteenth-century manuscripts, these connections are most concretely and minutely evident in sections containing passages translated from Arabic, paragraph by paragraph, sentence by sentence and even word by word, the latter taking the form of interlinear translation. Through an analysis of this volume’s content, language use and historical echoes, the chapter also argues for the need to look beyond the common, generalizing and flattening terminology of "Sri Lankan Malays." Deconstructing nomenclature and its history exposes the diversity of those sent into exile and enlistment in terms of language, place of origin and additional forms of affiliation.
More than ten years after the Liberia Truth and Reconciliation Commission (TRC) released its Final Report, there has been no implementation of the recommendations proffered. This article focuses on post-conflict memorialization, the TRC's strategy to engender collective remembering, and a set of State-led actions designed to teach future generations about the past violence with a view to preventing relapse into violent conflict. Both the constructive and destructive patterns of remembering that have evolved in the wake of the government's silence since the release of the recommendations will be analyzed.
Some of the greatest successes in infectious disease control rest on empirically grounded models of human and livestock infections. In contrast, disease control in wildlife has not always been as successful. Timely translation of knowledge into proposed management actions remains a challenge in several wildlife disease systems, one of which is pneumonia management in bighorn sheep throughout the North American West. Although pneumonia was recognised as a major impediment to bighorn sheep conservation >80 years ago, a series of challenges stymied the management decision-making process. Despite past obstacles, recent advances from long-term, intensive studies of marked individual sheep have motivated new interest in research-driven strategies for disease management in this system. The system provides an unusual opportunity to study an emerging pathogen disproportionately impacting immature animals through infections that originate from asymptomatically infected adult hosts. We tell the story of bighorn sheep pneumonia, emphasising the obstacles that historically hindered decision-making, the biological or logistical constraints underlying each decision point, and the particular empirical insights that clarified each constraint.
We investigated intestinal trichomonads in western lowland gorillas, central chimpanzees and humans cohabiting the forest ecosystem of Dzanga-Sangha Protected Area in Central African Republic, using the internal transcribed spacer (ITS) region and SSU rRNA gene sequences. Trichomonads belonging to the genus Tetratrichomonas were detected in 23% of the faecal samples and in all host species. Different hosts were infected with different genotypes of Tetratrichomonas. In chimpanzees, we detected tetratrichomonads from ‘novel lineage 2’, which was previously reported mostly in captive and wild chimpanzees. In gorillas, we found two different genotypes of Tetratrichomonas. The ITS region sequences of the more frequent genotype were identical to the sequence found in a faecal sample of a wild western lowland gorilla from Cameroon. Sequences of the second genotype from gorillas were almost identical to sequences previously obtained from an anorexic French woman. We provide the first report of the presence of intestinal tetratrichomonads in asymptomatic, apparently healthy humans. Human tetratrichomonads belonged to the lineage 7, which was previously reported in domestic and wild pigs and a domestic horse. Our findings suggest that the ecology and spatial overlap among hominids in the tropical forest ecosystem has not resulted in exchange of intestinal trichomonads among these hosts.
This chapter discusses the lives and letters of saints and bishops who were considered truth-tellers by their contemporaries. The selected letters and saints’ lives were written in Francia between c. 550 and c. 750. In addition, two hagiographic texts and one letter from Italy and Visigothic Spain are included to compare developments in Merovingian Francia with other kingdoms and regions of the former Western Roman empire. In the selected sources we encounter Gallo-Roman, Frankish, Visigothic, Anglo-Saxon and Irish holy men who ventured to criticise those in power. Although the rhetoric of these truth-tellers and the vocabulary of their biographers do not conform to classical standards, this chapter demonstrates that their frank speech and behaviour was very much related to the late antique tradition of free speech.
This final chapter discusses a letter, attributed to Pope Gregory IV (d.844), to the bishops of Francia. In 833, Pope Gregory IV made the journey across the Alps to mediate in the conflict between Emperor Louis the Pious and his sons. The chapter addresses the issue of the identity of the author who composed the letter. It discusses both the content of the letter and the details of its transmission, because this text is highly relevant to the reception of classical ideas on free speech. The unidentified author draws upon the late antique tradition of free speech in an attempt to persuade the bishops of Francia to speak out to the emperor. An analysis of this letter shows that the classical vocabulary of free speech, which disappeared in letters and literature of the Latin West after the sixth century, was reintroduced in political discourse. The chapter shows how within the ninth-century movement to bolster spiritual authority, the old vocabulary of free speech found a new place.
Leishmania rely heavily on glycans to complete their digenetic life cycle in both mammalian and phlebotomine sand fly hosts. Leishmania promastigotes secrete a proteophosphoglycan-rich gel (Promastigote Secretory Gel, PSG) that is regurgitated during transmission and can exacerbate infection in the skin. Here we explored the role of PSG from natural Leishmania-sand fly vector combinations by obtaining PSG from Leishmania (L.) major-infected Phlebotomus (P.) papatasi and P. duboscqi and L. tropica-infected P. arabicus. We found that, in addition to the vector's saliva, the PSG from L. major and L. tropica potently exacerbated cutaneous infection in BALB/c mice, improved the probability of developing a patent cutaneous lesion, parasite growth and the evolution of the lesion. Of note, the presence of PSG in the inoculum more than halved the prepatent period of cutaneous L. tropica infection from an average of 32 weeks to 13 weeks. In addition, L. major and L. tropica PSG extracted from the permissive experimental vector, Lutzomyia (Lu.) longipalpis, also exacerbated infections in mice. These results reinforce and extend the hypothesis that PSG is an important and evolutionarily conserved component of Leishmania infection that can be used to facilitate experimental infection for drug and vaccine screening.
Social network characteristics of people who inject drugs (PWID) have previously been flagged as potential risk factors for HCV transmission such as increased injection frequency. To understand the role of the injecting network on injection frequency, we investigated how changes in an injecting network over time can modulate injecting risk behaviour. PWID were sourced from the Networks 2 Study, a longitudinal cohort study of PWID recruited from illicit drug street markets across Melbourne, Australia. Network-related correlates of injection frequency and the change in frequency over time were analysed using adjusted Cox Proportional Hazards and Generalised Estimating Equations modelling. Two-hundred and eighteen PWID followed up for a mean (s.d.) of 2.8 (1.7) years were included in the analysis. A greater number of injecting partners, network closeness centrality and eigenvector centrality over time were associated with an increased rate of infection frequency. Every additional injection drug partner was associated with an increase in monthly injection frequency. Similarly, increased network connectivity and centrality over time was also associated with an increase in injection frequency. This study observed that baseline network measures of connectivity and centrality may be associated with changes in injection frequency and, by extension, may predict subsequent HCV transmission risk. Longitudinal changes in network position were observed to correlate with changes in injection frequency, with PWID who migrate from the densely-connected network centre out to the less-connected periphery were associated with a decreased rate of injection frequency.
This chapter covers the mathematical theory of how plane waves are reflected by boundaries or interfaces separating solid layers in the subsurface and how they are transmitted through them. Reflections off the Earth's surface are also discussed. The equations describing the physical boundary conditions that incident, reflected, and transmitted waves must satisfy are derived. The calculation of reflection and transmission coefficients, which give the amplitudes of reflected and transmitted waves, is covered. Polarity reversals and phase changes are discussed. Critical angles, which are related to the total internal reflection of incident waves, are studied. This is followed by coverage of the calculation of the amount of seismic wave energy that is reflected and transmitted, reflection and transmission of waves from liquid–liquid, liquid–solid, and rigid boundaries, and approximate formulas for reflection and transmission coefficients.
This chapter covers the computation of synthetic seismograms, or theoretical seismograms. This involves predicting, via computation, what seismic traces might look like for a given subsurface medium model. The relatively simple case of vertically traveling waves in a sequence of flat horizontal layers is discussed in relative detail, including how to compute wave amplitude losses due to reflection, transmission, geometrical spreading of wavefronts, and absorption. The generally more complicated case of nonvertically traveling waves is also briefly summarized. More complete methods such as the finite difference and finite element methods are briefly mentioned. Also covered are the reflectivity function and the interference effects that occur for waves with nearly equal arrival times, such as the tuning effect. The chapter ends with an appendix showing examples of synthetic seismograms computed with the finite difference method.
This article examines the attitudes of Warring States textual witnesses to the increase in presence of and reliance on bamboo manuscripts in communicating knowledge. Based on a rereading of transmitted materials and four manuscript texts (*Wuwang Jianzuo A and B, *Baoxun, and the Zhou Wuwang you ji) from the Warring States period, I analyze how contemporaries dealt with questions about the status of (manuscript) texts, their use and transmission, their trustworthiness, and their ability to preserve knowledge. These are texts that talk about themselves. They remark upon the physicality of text and the act of writing, the problem of oral and written transmission, and the differences in the ability of memory and manuscripts to store, hide, and reveal knowledge. I argue that these different reflections reveal a change in the predominant medium of communicating knowledge towards an increased reliance on bamboo manuscripts gradually and partially replacing traditional knowledge practices.
Mosquitoes are haematophagous vectors for hundreds of pathogenic viruses that are aetiological agents of human diseases. In nature, mosquito-borne viruses maintain a lifecycle between mosquitoes and vertebrate animals. Viruses are acquired by a naive mosquito from an infected host by blood meals and then propagate extensively in the mosquito's tissues. This mosquito then becomes a virus reservoir and is competent to transmit the viruses to a naive vertebrate host through the next blood meal. To survive in and efficiently cycle between two distinct host environments, mosquito-borne viruses have evolved delicate and smart strategies to comprehensively exploit host and vector factors. Here, we provide an update on recent studies of the mechanisms of virus survival in, acquisition and transmission by mosquitoes.
Increased social contact within school settings is thought to be an important factor in seasonal outbreaks of acute respiratory infection (ARI). To better understand the degree of impact, we analysed electronic health records and compared risks of respiratory infections within communities while schools were in session and out-of-session. A time series analysis of weekly respiratory infection diagnoses from 28 family medicine clinics in Wisconsin showed that people under the age of 65 experienced an increased risk of ARI when schools were in session. For children aged 5–17 years, the risk ratio for the first week of a school session was 1.12 (95% confidence interval (CI) 0.93–1.34), the second week of a session was 1.39 (95% CI 1.15–1.68) and more than 2 weeks into a session was 1.43 (95% CI 1.20–1.71). Less significant increased risk ratios were also observed in young children (0–4 years) and adults (18–64 years). These results were obtained after modelling for baseline seasonal variations in disease prevalence and controlling for short-term changes in ambient temperature and relative humidity. Understanding the mechanisms of seasonality make it easier to predict outbreaks and launch timely public health interventions.
Why some parasites evolve and maintain extreme levels of virulence is a question that remains largely unanswered. A body of theory predicts that parasites that form long-lived spores able to persist in the environment evolve higher virulence, known as the sit and wait hypothesis. Such parasites can obliterate their local host population and wait in the environment for further hosts to arrive, reducing some of the costs of high virulence. On the other hand, some models predict the opposite to be true, that virulence and environmental persistence are both costly and traded off, the resource allocation hypothesis. I conducted a meta-analysis on published data on the relationship between environmental persistence and virulence collected to date. I first examined all data available to date and then conducted a smaller analysis focussing on just those studies testing the specific predictions of the sit and wait hypothesis. Empirical work supports both hypotheses; however, the direction of the effect is largely associated with parasite type. In both analyses, viruses tend to show evidence of resource allocation trade-offs, these traits are positively correlated in bacterial and fungal parasites.
Media stories often reach citizens via a two-step process, transmitted to them indirectly via their social networks. Why are some media stories strongly transmitted and impact opinions powerfully in this two-step flow while others quickly perish? Integrating classical research on the two-step flow of political communication and novel theories from cognitive psychology, this article outlines a model for understanding the strength of political frames in the two-step flow. It argues that frames that resonate with cognitive biases (that is, deep-seated psychological decision rules) will be transmitted more and have a stronger influence on opinion when citizens recollect media frames in their social networks. Focusing on the case of episodic and thematic frames, the study tests this model. It introduces a novel research design: implementing the children’s game ‘Telephone’ in consecutive experimental online surveys fielded to nationally representative samples. This design helps gauge the reliability of transmission and the degree of persuasiveness in actual chains of transmission.
Mycobacterium ulcerans is recognised as the third most common mycobacterial infection worldwide. It causes necrotising infections of skin and soft tissue and is classified as a neglected tropical disease by the World Health Organization (WHO). However, despite extensive research, the environmental reservoir of the organism and mode of transmission of the infection to humans remain unknown. This limits the ability to design and implement public health interventions to effectively and consistently prevent the spread and reduce the incidence of this disease. In recent years, the epidemiology of the disease has changed. In most endemic regions of the world, the number of cases reported to the WHO are reducing, with a 64% reduction in cases reported worldwide in the last 9 years. Conversely, in a smaller number of countries including Australia and Nigeria, reported cases are increasing at a rapid rate, new endemic areas continue to appear, and in Australia cases are becoming more severe. The reasons for this changing epidemiology are unknown. We review the epidemiology of M. ulcerans disease worldwide, and document recent changes. We also outline and discuss the current state of knowledge on the ecology of M. ulcerans, possible transmission mechanisms to humans and what may be enabling the spread of M. ulcerans into new endemic areas.